7
Julius Caesar was per haps the greatest in a long line of competent Roman generals. Because of the commentaries he left, we know more about intelligence activities during his era than about any other time in the Roman Republic. Caesar used all the means available to set up a communications network to support his military machine. His efficiency and speed were exemplary, and he, as much as anyone, understood how tradition-bound and inflexible both the Roman military and political apparatuses could be. His contacts with numerous foreign princes gave him ample opportunity to observe other intelligence systems. By breaking Roman intelligence activities down into their component parts, we are better able to summarize and evaluate the Roman Republican system and Caesar’s contributions to it.
Scouts and reconnaissance
The evidence clearly shows that Roman commanders in the field did perform reconnaissance, and that they used scouts and spies. They had the ability to collect intelligence, make decisions based on it, and transmit it to the capital. But these things were never institutionalized, and until the last century of the Republic, Roman scouting could still be comparatively ineffective. On many crucial occasions, the Romans were caught on terrain that rendered their deployment so difficult that they were unable to dictate the course of the engagement. A simple thing like the direction of the sun, dust, and wind had to be considered, as the Romans learned well at Cannae, for example, where the prevailing wind both blinded the Roman troops and disguised Hannibal’s soldiers.1 Roman scouting parties were used more frequently after the Punic Wars, but with mixed success.2 All too frequently scouts were ambushed by enemy reconnaissance units that were out looking for them.3 Commanders such as Octavian did their own reconnaissance work, a dangerous practice at best.
In Caesar’s army, the majority of the scouting and reconnaissance efforts were performed by exploratores. Formerly part of the cavalry, they were detached to go on specific missions. Their primary job was to locate the enemy. Caesar does not specify in his Commentaries how many individual scouts made up a scouting party, but he always speaks of them in the plural. Since they came from cavalry units, they were mounted and could locate enemy positions at distances of up to 24 miles away.4 He sometimes used allied scouts from friendly Gallic tribes instead of his own, although he would also include a trusted centurion with the scouting detail.5 Because Caesar’s scouts, along with his cavalry, consisted of foreign troops, these centurions acted as a double check on the scouts’ accuracy and loyalty. In one instance, this system failed when a centurion detailed with the scouts panicked and falsely reported that an important hill was occupied by the enemy.6 Gallic armies were enormous in size, and so Caesar was constantly tracking enemy forces within a fluid and changing situation. Scouts, for example, reported on the progress of enemy river-crossings or on the moving of their camp.7
Reconnoitering the terrain was important because the Romans placed a premium on occupying the advantageous position. Caesar always tried to place his camp on the high position of a gently sloping hill. The camp also had to be close to water and near enough to a forest to provide wood and timber. Caesar’s allied scouts, accompanied by centurions, performed this reconnaissance for suitable campsites.8 During the campaigns of 52 bc against Vercingetorix, Caesar learned from scouts the topographical features of an important hilltop, which he was later able to capture.9 In 51 bc against the Germans, he discovered when hilltops were abandoned and could be captured safely.10
While Caesar has often been criticized for not realizing the full potential of cavalry in battle, most of his critics have failed to appreciate the role of his cavalry in intelligence gathering.11 Caesar employed indigenous troops that specialized in cavalry operations; they were naturally more familiar with the topography, climate, vegetation, trafficability of terrain, and other local conditions, and they could offer more useful advice on the peculiar features of their native territory. Caesar’s entire cavalry often performed reconnaissance functions in addition to protecting the legion’s flanks and pursuing a retreating enemy. A case in point was the battle against the Belgae in 57 bc, when Caesar, confronted by an enemy force of overwhelming size, and aware that the Belgae were the fiercest and bravest of the Gauls, instructed his cavalry to engage in daily skirmishes to probe the enemy’s strength, as well as to boost his own men’s confidence.12
Spies and espionage
Although Rome’s propaganda portrayed the use of spies as something “foreign,” that is, used by people such as Tarquinius Superbus and Hannibal, the Romans did make use of them and their deployment became more frequent by the end of the Republic. The episode of Gaius Laelius infiltrating the camp of Syphax described in Chapter 3 above is just one example. Both Cato and Sertorius used spying successfully and yet it was considered so unusual that Sertorius was decorated for valor. While fighting the Gauls with Marius, he put on Celtic dress, learned a few of their more common expressions, and mingled with the barbarians. He then reported back to Marius. He was rewarded for both his judgment and daring.13
If introducing agents among the enemy was not possible, an alternative was to recruit spies from among the enemy. Large cities fortified with garrisons fell more easily to subterfuge than to siege. The general pattern was to locate a disenchanted faction within a beleaguered town and persuade it to either open the gates or otherwise to betray its own people. Sosistratus of Syracuse became a traitor in one example. In 212 bc, during the siege of Syracuse, he was bribed by the Roman commander, Marcus Marcellus, to reveal that the city guards were less strict on a certain holiday when wine and food were being distributed. Marcellus then took advantage of the gaiety, had his men scale the walls, killed the sentinels, and throw open the gates for the Roman Army.14 A second example of infiltration occurred in 272 bc, when Milo, holding the town of Tarentum, was approached by the consul, Papirius Cursor, and promised safety to his townspeople if he would deliver his city over to the Romans. Persuaded by the offer, Milo convinced the Tarentines to send him as ambassador to the Romans and he delivered the city over to them unguarded.15
Caesar’s spies consisted mainly of speculatores. Although he refers to them only twice in The Gallic War, they certainly were part and parcel of his intelligence assets. That they are not mentioned more frequently probably means that their effectiveness was taken for granted and their missions may have been clandestine. It has been suggested that each of Caesar’s legions had ten speculatores under its command based on later practice, but we do not know this for a fact.16 Though the word speculator is often translated as “spy,” their primary, overt assignment was to deliver dispatches both to Rome and between camps, such as the one Labienus sent alerting Caesar to the revolt of the Belgae in 57 bc.17 The speculatores probably carried messages of intelligence value and operated surreptitiously, especially when traveling through hostile territory. Men were selected for service as speculatores on the basis of their loyalty and discretion, and they would be the obvious choice of personnel to engage in espionage or exceptionally sensitive reconnaissance missions. Caesar’s speculatores gathered information about possible rebellions, and were the most likely sources whenever Caesar states, as he often does, that he “received frequent rumors”18 or that he received “a certain report.”19
That speculatores delivered dispatches is clear. When Caesar was at Ruspina in the African campaign of 47 bc, we know he issued orders through the speculatores;20 and on other occasions had the speculatores stand by to deliver orders.21 Speculatores also undertook secret reconnaissance missions and operated in advance of the main army. At the Battle of Munda, in 45 bc, they informed Caesar that the enemy forces had been in battle formation since the early morning hours.22 After Caesar defeated the forces at Munda, his cavalry and infantry on pursuit sent speculatores ahead to track the retreating enemy. In the African campaign, too, we see speculatores and forward cavalry patrols observing enemy positions and reporting to Caesar.23
Although Caesar’s speculatores performed mainly reconnaissance and messenger duties, they were also employed as spies.24 Caesar apparently turned to speculatores whenever secrecy was imperative. In 57 bc they advised him that a large assembly of Belgae were breaking camp and leaving the area. He kept his own army and cavalry in camp, because he feared an ambush. But at daybreak, once the information had been confirmed by reconnaissance, he ordered his cavalry forward to delay the enemy’s rear guard.25 Similarly, in 54 bc, when he marched with 7,000 men to relieve Q. Cicero’s besieged camp, which was surrounded by more than 60,000 Gallic soldiers, Caesar’s speculatores fanned out to seek the safest route for crossing a valley that led to Cicero’s camp. Outnumbered by about eight to one, Caesar had to keep this reconnaissance secret so that his men would be less vulnerable to ambush while moving through the valley.26
When speculatores engaged in espionage, they were treated very differently from ordinary soldiers, as is reflected by their fate after capture: they were executed. During the African campaign the Pompeian general, Scipio, sent two Gaetulians to spy on Caesar, but the Gaetulians turned themselves in to Caesar and were not harmed.27 In two other cases, however, speculatores were captured and summarily executed. Evidently Caesar exercised his prerogative of dementia with greater circumspection when confronted by a hostile intelligence operation. In the Spanish campaign of 45 bc, the author of The Spanish War matter-of-factly states that “a spy [speculator] from the Second Legion on Pompeius’ side was captured by our troops and put to death.”28 Later he recounts that the following night “some scouts [speculatores] were caught – three slaves and one soldier from a native legion. The slaves were crucified, the soldier beheaded.”29
Traitors, prisoners of war, and deserters
Prisoners of war had always been a source of information since earliest times. While much could be gleaned about the enemy’s plans and intentions by interviewing prisoners, Caesar did not take their information at face value; he recognized the need to evaluate and verify intelligence, especially from such sources. He frequently questioned a number of prisoners and collated their stories to assess their reliability.30 In the Commentaries he does not discuss methods of interrogating prisoners, but torture was probably applied occasionally.31
Interpreters were usually needed to assist at interrogations as well as at conferences. The interpreters attached to Caesar’s general staff were mostly enfranchised Gauls, and other bilingual troops who were very likely available in the cavalry. In cases of exceptionally delicate negotiations, however, only Roman interpreters were present. For the critical talks with Diviciacus, Caesar says he dismissed his regular interpreters and instead sent his close friend, Gaius Valerius Procillus, in whom he had absolute confidence.32 On another occasion, during an ambush in which the Fourteenth Legion was destroyed, Sabinus sent his interpreter Gnaeus Pompeius to the Gallic general to plead for mercy.33 Such bilingual agents posed as envoys and were sometimes arrested as spies and risked execution.34
The information obtained at interrogations could often prove crucial. In his campaign against Ariovistus in 58 bc, Caesar questioned prisoners and learned that the German soothsayers had predicted that they were destined to lose if they fought before the new moon.35 With this psychological edge, Caesar forced a battle the following morning and won. He also used prisoners and deserters by sending them back to discover details of the enemy defenses. In his last major campaign in Gaul against Vercingetorix, deserters and prisoners provided crucial intelligence. Having just begun the siege of Alesia, Caesar was informed that Vercingetorix had detached his entire cavalry to guide reinforcements to his location, and that he intended to hold out until those reinforcements arrived. The prisoners revealed that Vercingetorix had about 65,000 men in Alesia, and that there were only enough rations for about thirty days.36 Armed with this information about the enemy’s plans and condition, Caesar prepared not only to meet the Gallic relief army to his front, but also to protect against a rear attack from Alesia. The 250,000–strong Gallic reserves did arrive, but Caesar’s legionnaires emerged victorious after three days of fierce fighting. The siege of Alesia is one of the most extraordinary operations of the Gallic Wars, and intelligence from prisoners was the key to its success.37
Many other examples show Caesar learning from prisoners about enemy plans to ambush his forces. Roman foraging parties were most vulnerable to ambush, since they sometimes searched for supplies far away from camp. Early in the campaign of 52 bc, during the siege of Avaricum, prisoners reported that Vercingetorix, who was encamped some 16 miles from Avaricum, had left camp to spring an ambush because he was expecting the Romans to foray the following day. Capitalizing on Vercingetorix’s absence from camp, Caesar attacked the Gallic position.38 Again in 51 bc, while campaigning against Correus, the leader of the Bellovaci, prisoners disclosed that Correus had marshaled over 7,000 men to ambush the Roman foragers.39 In Caesar’s own words, “because they knew what the enemy plan was, our men were mentally and physically ready for the fight. Knowing that the legions were coming up from behind them, they were ready for any attack.”40 We also know that Caesar later incorporated reports from prisoners in his writings: he often cites them as ex post facto sources in the Commentaries. Their information helped him reconstruct past events where only Gallic eyes and ears had been present41
Caesar makes several references to deserters (perfugae) in The Gallic War, and he must have dealt with them throughout the campaigns.42 Deserters were generally considered ill-informed unless they were high-ranking enemy personalities. Caesar distrusted deserters because they were known to exaggerate or even to fabricate stories to save their lives, by appearing to be useful. When Caesar did listen to what they had to tell, he would always verify their accounts through other sources. During the siege of Alesia in 52 bc, deserters as well as prisoners informed Caesar of Vercingetorix’s plans.43 In the struggle with Vercingetorix at Gergovia in the same year, Caesar ascertained both by scouting and from deserters that the far side of a certain hilltop afforded partly covered access to the enemy’s rear, before launching an assault to capture the hill.44
In his work The Civil Wars, Caesar lists deserters as more profitable sources than in the Gallic Wars, and they are mentioned much more frequently. Their importance was due to their higher rank; they were men who could reveal valuable details about the enemy’s plans. In Africa near Ruspina in 47 bc, “a large number of men of all classes” defected to Caesar and from these “the enemy’s plans were learned.”45 In addition, during Caesar’s siege of Ategua in Spain in 45 bc, the author of The Spanish War notes that a military tribune, Q. Marcius, and a Roman knight, C. Fundanius, defected to Caesar.46 A constant stream of high-ranking defectors with recent access to the enemy decision-makers undoubtedly kept Caesar well informed about the enemy’s plans and capabilities. Such information was regularly checked against that of other captives, local inhabitants, or Caesar’s spies.47 The cultivation of these sources paid off handsomely. In the African campaign, near the town of Uzitta, an informer told Caesar that the local inhabitants stored grain in secret underground cellars. Caesar then ordered two legions with some cavalry to steal grain from those cellars to feed his troops. Having detected this action by observing Caesar’s men return, the enemy laid ambushes on the assumption that the Caesarians would make additional trips for resupplies. However, deserters informed Caesar of the ambushes too, and he was able to spring an unexpected counterambush, killing over five hundred of the enemy.48
Caesar makes less mention of prisoners in The Civil Wars and places little emphasis on their contribution of intelligence. In this respect, The Civil Wars is a direct antithesis of The Gallic War. Since Caesar had so many deserters willingly providing information, it was presumably less efficient to exploit prisoners under duress. Caesar’s aim was to enroll the prisoners in his own army, and for this reason he welcomed them as comrades, not as prisoners of war. He treated them humanely because they were still more useful as sources of information than as martyrs for the enemy cause. There are several examples of intelligence from prisoners being of operational benefit to Caesar. During the campaign near Ilerda in 49 bc, Caesar’s cavalry captured a Pompeian watering party that had ventured too far from camp. These prisoners reported that their comrades were secretly breaking camp. Cleverly, Caesar sounded the signal for his own troops to decamp. When the enemy heard Caesar’s signal, they aborted their own planned night movement, afraid that they would be attacked.49 The enemy apparently never discovered how Caesar received early warning of their plans. The next day at a council of war, another suggestion for a night movement was rejected because the previous night had proven that it was impossible to get away secretly.50
Nonmilitary sources: ambassadors, diplomats, merchants, and aristocrats
In the absence of an established civilian intelligence service during the Republic, the Romans made use of such established official channels as diplomats and envoys. In addition, there was the informal network of merchants carrying on business and aristocrats traveling abroad, who brought news of foreign developments. The weakness of the diplomatic approach to intelligence gathering has already been discussed in Chapter 4. There was no doubt in the minds of those who received these diplomats that spying was one of their duties.
How well informed the Romans were often depended on how they perceived their own interests. The Romans were quite capable of avoiding foreign entanglements or ignoring military situations abroad, if their attention was directed elsewhere or if their was no immediate gain. This lassitude served well enough in offensive situations during the Republic, such as Rome’s dealings with the Hellenistic East. It worked less well in defensive situations, when advance warning of impending attack or of dangerous barbarian movements was needed. Roman reliance on allies for information was neither prompt enough nor reliable enough to be entirely adequate.
Communications security: codes, ciphers, secret messages, and transmission
Several ingenious methods of sending secret messages are attributed to the Romans in the Republic. Among the methods they employed were writing messages on hides sewn on the bodies of game or sheep that were then driven to a place where the message could be retrieved.51 Messages were reportedly stuffed under the tails of mules in order to get them by the pickets52 and still others were written on the linings of scabbards.53 We must consider the possibility that most of the examples that come from the later Roman historians Frontinus (first century ad) and Vegetius (fourth century ad) and date back to the Republic or earlier may represent apocryphal incidents that are meant to demonstrate how clever the great generals of the past really were.
These incidents are both numerous and amusing. In the war against Mithridates, for example, the Roman commander Lucullus sewed letters inside two inflated skins and then ordered one of his soldiers, a skilled swimmer, to join the skins and cross a 7-mile river on them. According to this story as told by Frontinus and others, the swimmer was so successful at steering the skins that the sentries mistook him for some sort of marine creature.54 The consul Hirtius sent letters inscribed on lead plates to Decimus Brutus, who was besieged by Antony at Mutina. The letters were fastened to the arms of soldiers who swam across the Scultenna River.55 Hirtius also shut pigeons in the dark, starved them, and then tied letters to their necks by a hair. When they were released near the city walls, the birds, eager for light and food, sought the highest buildings, where Brutus received his messages.56 If he placed food regularly on the same spot, the pigeons would return there and bring a steady flow of information.57 We are never told, of course, how the pigeons were trained to fly back to the starting point.
The Greek cipher used by Caesar is the only instance of a cryptographic system dating to the Republic. In his message to Q. Cicero in 54 bc, sent while Caesar was marching with two legions to relieve Cicero’s camp, he wrote the letter in Greek characters, “so that if it were intercepted the Gauls should not discover what our plans were.”58 The letter was to be attached to the thong of a spear and thrown inside the rampart. This message was probably first transliterated into Greek and then rendered in Caesar’s mono-alphabetic substitution cipher. According to Suetonius, Caesar used such a system regularly, and Augustus is said to have modified the system.59
When Caesar laid siege to Dyrrachium he used an elaborate network of beacons for the transmission of military intelligence, similar to the one that had served Scipio Aemilianus in Spain when he was beleaguering Numantia in order to blockade the enemy and to prevent it from breaking through. He signaled by smoke from one fortification to the next, in addition to sending reports.60 At the same time, appreciating the effect of timely news about his victory in the eastern and western provinces, his messengers were standing by ready to travel and spread the news of the blockade.61 Caesar presumably aimed at spreading the news in the near eastern provinces and in Rome in order to weaken Pompey’s position. Such propaganda, however, worked both ways. It was Pompey who won the battle and promulgated news reports and public announcements to celebrate his victory and tell the world about it.62 This competition for the hearts and minds of the public by disseminating partisan news from the front illustrates the importance of fast communications and the nervous strain on the population during the civil wars.
When Caesar won at Pharsalus in Thessaly, Pompey fled to Egypt. Caesar, again quicker in the rapid intelligence war, knew the effect good or bad news from the battlefield would have in Rome. For the first time in Roman history he organized a regular information service by messengers on horseback posted in advance at set intervals. He made it possible to send dispatches from Thessaly to Messana in Sicily, which was threatened by the Pompeian fleet, to help boost the morale of the defenders. News of the victory and further progress of the campaign probably reached Rome by the same means since in all probability Caesar had organized relays of horsemen from Brundisium to Rome. From there, in similar manner, the message was forwarded to all the western provinces. This system, never explicitly depicted by Caesar, is inferred by Dvornik from his stated intention to spread everywhere the word of his successes, and from his report that Pompey did likewise after defeating Caesar.63 Although Caesar was short of cavalry after his campaign in Greece, he did not hesitate to detach a considerable number of horses in order to establish this relay system.
That this earliest Roman model of a regular, orderly information service emerged in the former Antigonid kingdom may not be coincidental. Dvornik has suggested that the example of Philip V of Macedon might have inspired Caesar to establish his own service, as traces of this older system survived in Macedonia long after the downfall of Philip and Perseus.64 Caesar certainly recognized the possibilities of such a service. He reports that Vibullius, on his journey to meet Pompey with peace proposals, was riding day and night changing horses at every town.65 These stations and their fresh horses were certainly not maintained by the state. But the fact that they still existed after the disintegration of the Macedonian Empire suggests that enterprising private citizens may have taken over the institution established by their kings and continued the service, which promised a good profit because there were no other means of rapid transport.66 Caesar himself used this private network of communications, which had evolved along Roman military roads, but he also introduced into the Roman information service an official post to convey intelligence, a service paid for by the state and, in this first prototype, operated by Roman cavalrymen.
Defensive counterintelligence: Installation security
Installation security was definitely a Roman strength. The Romans learned early and well the benefits of building a secure camp at the end of every day’s march. The Roman camp was considered one of the best defenses against a surprise attack and against spies.67 Once the sentries were on duty it was extremely difficult to sneak in or out of camp. Indeed, detecting enemy spies and agents both in the camp and outside it was the first objective of Roman counterintelligence. The simplest way to identify a spy inside a camp was to have everyone account for another person in the camp. The odd man out was presumed the infiltrator. Variations of this theme were supposedly employed by Caecilius Metellus in the First Punic War68 and by Mummius after Corinth.69 Can we seriously assume this “buddy system” was the most sophisticated method of uncovering spies in the Republican period? The sight of 5,000 legionaries in a camp running to their tents in search of their partner is not convincing. With foreign auxiliaries and mixed contingents, other mechanisms for identification must surely have been devised.
A general must be able to detect not only foreign spies within his camp, but also any seditious soldiers.70 Roman mutinies were common, despite the army’s reputation for fidelity and the severe punishment that awaited troublemakers.71 Such undesirable personnel were uncovered by tribunes, their lieutenants, or other officers of undoubted loyalty. The culprits were then detached for other duty, preferably doing something they liked so that they would not suspect they were in disfavor.72 Once a mutiny actually broke out, the ringleaders were disposed of immediately as an example to the others.73
Operations security and censorship
As Vegetius said on operations security: “Those designs are best of which the enemy are entirely ignorant until the moment of execution. Opportunity in war is more to be depended upon than courage.”74 To create an opportunity, one must be sure the enemy is not forewarned; once an adversary had discovered the plans, it was best to abort the operation. A general had to keep his plans secret for as long as possible, and this secrecy meant, first of all, keeping them from the rank and file. Pithy examples abound in Frontinus of commanders like Metellus Pius, who would not reveal his plans for the following day to his own men, and who remarked: “If my tunic could tell, I would bum it.”75 Or Crassus, when asked by a soldier at what time they would break camp in the morning, replied: “Are you afraid you’ll not hear the trumpet?”76 These stories are probably apocryphal, but they prove in an amusing way that the Romans were well aware of the security risks involved in letting their plans leak out. Whatever their level of security consciousness, it did not prevent Hannibal’s spies from discovering both Roman intentions and the consuls’ disagreements over the conduct of the war, as we have seen in an earlier chapter.
One tradecraft technique, attributed to Gaius Marius but applicable in other places, was to forward instructions to allied troops in a two-part letter. The first part of the letter ordered them to leave the second part sealed until a certain date. The letter was presumably in codex or book form, with the second and third leaves fastened together by a special seal. Afterwards, but before the appointed time, he demanded the letters back and, finding the inner seals broken, knew that treachery was afoot.77
Censorship also took the form of hiding the news of defeat from troops who were fighting elsewhere. Early examples show commanders distorting information to turn bad news into good for their own purposes. Perhaps the best illustration of how serious the Romans could be about not letting news slip out was the incident in which Sertorius plunged a dagger into a barbarian messenger who had reported a Roman defeat, because he did not want the news to spread to his men and to dampen their morale.78
Offensive counterintelligence: Deception
Deception was a major component of Caesar’s active counterintelligence measures, especially in the Gallic campaigns when he was grossly outnumbered and had to count on the element of surprise as a force multiplier to offset the enemy’s overwhelming strength.79 If the Romans despised the notion of trickery in war and diplomacy, we would never know it by reading The Gallic War.
A prime example of this tactic is seen in 54 bc, when Caesar, with only 7,000 troops at his disposal, was confronting a Gallic army over 60,000 strong. As he was approaching Q. Cicero’s surrounded camp, the Gauls abandoned the siege and turned toward Caesar. To lull the Gauls into a false sense of security, Caesar built his camp much smaller than usual and instructed the soldiers to feign confusion and mock fear. The Gauls, deceived by this show of timidity, foolishly rushed the camp in triumphant disorder. Caesar then unleashed his cavalry and legionaries in a sudden counterattack from the camp. The enemy, completely surprised by the vigor of the Roman assault, fled in disarray.80
The Gallic War also tells how Caesar’s subordinates used deception, suggesting that by the late Republic it was standard Roman practice. In his campaign against the Parisii, Labienus sent his noisy baggage train and loudly splashing boatmen up a river, while the main body of the army marched quietly in the opposite direction and thus completely fooled the Gallic leader, Camulogenus, who was regarding the Roman plan.81 In the same vein, when Indutiomarus, chief of the Treveri, was besieging Labienus’s camp, the Roman commander took great care to keep him in ignorance of the arrival of reinforcements. Labienus held back his men until the enemy became overconfident, and then he launched a fierce sally from the camp to overpower the Gauls. Labienus had simulated fear, a trick whose repetition, one historian notes, “never seemed to make it stale.”82 The ruse worked for Labienus, and the death of Camulogenus caused his army to disperse.83 The following spring, in 53 bc, Labienus faced a superior Treveran army. Both Gallic and Roman forces were camped beside the same river. Knowing that Celtic reinforcements were approaching, Labienus said openly that he would not risk battle, but that he would break camp the next day. He deliberately did not strengthen the guard and his words leaked to the enemy, as he had intended. The following morning he instructed the tribunes and centurions to make more noise than usual to convince the Treveri that the Romans were departing in confused retreat. As the enemy carelessly harassed his rear guard, Labienus turned his legions and cavalry on the Treverii and routed them.84
A similar ploy worked well for another of Caesar’s lieutenants, Sabinus, in November 56 bc. Outnumbered by the Veneti but on higher ground, Sabinus declined to join battle. He chose a Gaul from his auxiliary troops to fake desertion and to confirm the enemy’s belief that the Romans were frightened and were planning to sneak out of their camp. The following day, the Gauls, tricked by this ruse, foolishly attacked Sabinus’s hilltop positions; the Romans suddenly counterattacked and won an easy victory.85
Psychological operations
Caesar’s psychological operations, especially during the civil wars, relied heavily upon manipulating information, both public and clandestine. People followed the progress of each side closely and were swayed by information about who was the most recent victor. As long as the struggle between Caesar and Pompey was unsettled, the populace in Rome ostensibly favored Caesar because his troops were stationed there. Dio tells us that whenever a victory by Caesar was announced the citizens rejoiced, and whenever a reverse was reported, they grieved; some were sincere and others feigned loyalty, “for there were many spies and eavesdroppers prowling about, observing all that was said and done on such occasions.”86 Envoys from both camps were continually shuttling back and forth, hoping to sound convincingly justified in the complaints they were raising against their foes, and at the same time to spy upon each others’ position.87
When Pompey boarded ship at Brundisium to join his troops in the East, the local population favored Caesar, and while embarkation was proceeding they signaled reports to Caesarian outposts about what was taking place. This kind of cooperation proved a valuable source of intelligence throughout the war. Caesar’s success in luring defectors from Pompey’s army was also highly profitable. In addition to providing tactical intelligence, defectors contributed strategic intelligence that was useful in Caesar’s conduct of psychological operations.
To influence popular opinion, Caesar captured the public’s attention with news by sending many dispatches to Rome during these wars. Such reports kept the public and the Senate apprised of the military situation, and also bolstered Caesar’s image. Caesar alluded to his psychological operations at Dyrrachium in 48 bc, when he wrote that part of his strategy was to have the word spread around that Pompey was blockaded by him and would not dare to venture out to fight.88 In the context of both military intelligence and political intelligence efforts, Caesar’s agents were pervasive. By 48 bc they were already monitoring the activities of Cicero, another one of Caesar’s political adversaries. In July of 46 bc Cicero noted in a letter that his epigrams were reported to Caesar, who could distinguish between those truly composed by Cicero and those falsely attributed to him.89
Caesar carefully edited his own writing to promote these propaganda objectives. Any suggestion that his men were disloyal was suppressed. Except for the mild disciplinary measures that followed the panicked rout at Dyrrachium, there is no hint in either The Gallic War or The Civil Wars that anything resembling a court martial ever took place in Caesar’s army. He never mentions the two famous mutinies of the civil wars, namely that of the Ninth Legion at Placentia in 49 bc or of the Tenth Legion at Rome in 47 bc.90 (Discipline and morale have been central problems of army management throughout history; unfortunately, we know very little about Caesar’s methods.)
Psychological warfare included using direct propaganda aimed at the enemy soldiers. Dio Cassius reports that Caesar tried to subvert both the local and Roman troops of Scipio Nasica in Africa, promising pardon and offering rewards to deserters, a rather modern-sounding device. Dio cynically adds that Scipio also circulated pamphlets in imitation of Caesar, but the trick failed because he did not promise them any reward, but merely urged them to “liberate the Senate and the Roman people.”91 The usual means of propagandizing ordinary soldiers was oral, as many of the legionaries in those days were still illiterate, but there could be reasonable expectation that written propaganda material would be read to the troops by any of their literate comrades. Perhaps when it was a question of tampering with the loyalty of someone else’s army, more security was needed even if it reached only a limited proportion of the audience.92
Another psychological ploy, used by Scipio Africanus against Hannibal (see Chapter 3), involved capturing a spy, in this case Lucius Messius, who was then shown around Caesar’s camp and later released to report its strength to Pompey.93 Caesar’s use of propaganda could also involve playing upon others’ superstitions. The Commentaries do not mention any religious ceremonies preliminary to important decisions, as found in Livy, and Suetonius confirms that no regard for religion ever stopped or delayed Caesar.94 This behavior is in complete contrast to his exploitation of enemy superstitions in The Gallic War, in which he forced a battle with Ariovistus as soon as he learned that the Germans were waiting for the favorable omen of the new moon; he knew that no man fights well who believes the gods have predestined him to defeat. Caesar did not worry about the sacred chickens, but he did not make the mistake of assuming that no one else worried about them.
Caesar’s propaganda campaign was effective, among other reasons, because it highlighted the cruelty of the Pompeian commanders. After the Battle of Dyrrachium, for example, Pompey handed the prisoners over to his lieutenant, Labienus, who insulted them and then had them all killed.95 This harshness encouraged desertions from the Pompeian camp and hardened the resistance of any Caesarians who were threatened with capture. During the African campaign of 47 bc, one of Caesar’s ships strayed off course and was later captured near Thapsus. A number of veteran troops and new recruits were brought before the Pompeian commander, Scipio. The centurion in charge of the group refused an offer to serve in Scipio’s army, and instead proposed a contest with himself and nine other Caesarian centurions against a cohort of about four hundred men from Scipio’s forces. This reply infuriated Scipio, and he had all the veteran soldiers tortured to death.96 Caesar, of course, did not overlook these outrages in his narrative.97
Speed
Caesar’s use of speed and innovation distinguished him from most other Roman commanders. He was a master of improvisation, often acting on impulse and instinct that could place his soldiers in awkward situations. When a civil war seemed imminent, Caesar’s adversaries expected that he would await the arrival in Ravenna of his legions from Gaul. Instead, with no more than a single legion at hand, he raced south and threw Rome into convulsions. Similarly, after the conquest of Spain, he raced to Brundisium in spite of the wintry weather, an insufficient number of transports, and the fact that several legions were still on their way to rendezvous with him.98 Notwithstanding his delicate health, Caesar was indefatigable. He worked and slept in his carriage while campaigning. Plutarch is full of admiration for his endurance and speed of travel, how he slept mostly in moving litters, and also gave dictation to two slaves simultaneously while traveling during the day. He moved so rapidly that on his first journey from Rome to Gaul, he reached the Rhone in seven days.99 Suetonius also tells us Caesar covered great distances with incredible speed, making 100 miles a day in a hired carriage and with little baggage, swimming the rivers which barred his path or crossing them on inflated skins, and very often arriving before the messengers sent to announce his coming.100 Plutarch and Suetonius describe Caesar’s journeys and demonstrate the efficiency of his communications. Since there was no state postal system, Caesar hired private carriages on his journeys, hired from enterprising citizens who made a living by supplying equipment to travelers. This means of transport served him well on his fateful journey from Ravenna to the Rubicon River.101
Learning tradecraft
The important thing to remember about the Roman Republican Army is that it was not a professional standing army, but was made up of levies called by the consuls when needed. Commanders of Republican armies could be surprisingly deficient in professional knowledge that makes their enormous successes all the more striking. The aristocratic Roman society into which they were born did not hold technical qualifications in high regard. Their social class did, on the other hand, attach value to versatile experience, and its young men were obliged to undergo military training.102 This was not enough to prevent most Republican wars from meeting with disasters at their beginnings, however triumphantly they were to conclude.103
Where did Roman generals learn the craft of intelligence? When appointed to command an army, a commander would have to acquire the pertinent skills himself from textbooks or from the harder lessons of personal experience. Cicero recounts the classic example of how Lucius Lucullus devoted his early years to legal studies and a quaestorship in which he saw no military action, and was then posted off to the Mithridatic Wars. He spent the entire voyage partly in acquiring advice from experienced men, partly in reading the achievements of others, and arrived in Asia “a made general,” although he had been ignorant of military affairs when he left Rome.104
Polybius enumerates three avenues to capable generalship, all of which included the mastering of intelligence techniques: (1) experience in the field, especially against an enemy like Hannibal, who was an expert at intelligence gathering; (2) advice from knowledgeable men; and (3) consultation of handbooks, although during the Republic the ordinary Roman praetor or consul had little familiarity with reading such treatises, which in any event were not considered reliable material. Toward the close of the second century bc, Marius mocked the sons of the nobility who were prepared to lead armies after reading Greek treatises on tactics: “I personally know of men, citizens, who after being elected consuls began for the first time to read the history of our forefathers and the military treatises of the Greeks.” In other words, they got things the wrong way round. One should carry out the duties of an office only after one has been elected to it, but practical experience and action should come first.105 Such manuals were either in vogue or just coming into vogue in Marius’s time. In the early Republic the Greek works were not yet available to a wide Roman audience, and the famous Roman compilations did not appear until later.
Of all people, Caesar was one who would have appreciated a rapid information service and might have been expected to reorganize Roman intelligence activities, but it was not easy to break old habits. His contacts with numerous Roman provinces gave him ample opportunity to observe their communications systems, and much has been written about Caesar’s attempts to introduce Hellenistic practices to Rome. Had Caesar lived longer, he might have instituted an intelligence service patterned on the eastern model in his new empire; but as with all questions involving what Caesar might have done had he not been assassinated, this is an exercise in pure conjecture.
Caesar and the end of the Republic
Rome went from being a city-state with an adult male population of about a quarter of a million people in 300 bc to being an empire that ruled over 50 million people. This could not have happened without pervasive changes taking place at all levels of society. And it is within the context of these changes that we look for the development of institutions that were used for intelligence gathering. The last century of the Roman Republic (100–31 bc) especially, brought with it major changes in the social structure of Roman society. The rapid expansion through conquest brought along with it provinces to administer, opportunities for the aristocracy to increase their wealth many fold, new institutions such as a professionalized army, an emergent bureaucracy, and finally repeated civil wars, which led to a monarchy.106
First, we must examine the army. Up to 107 bc it consisted, in principle, of peasant landholders who had originally only served in the fighting season. Extended wars with foreign powers necessitated longer terms of service and peasant-soldiers were forced to neglect their holdings. At the same time, the wars of foreign conquest brought immense wealth to Rome and this wealth was invested in land; moreover, prisoners of war recently enslaved could be used as an alternative source of labor to the peasant-soldiers. But instead of the average citizen-soldier being enriched, peasant land was bought up by the upper classes with war profits, the free peasants were dispossessed, and their land was concentrated into plantations called latifundia, which grew new commercial crops such as grapes and olives, or which raised horses. As more landowners were dispossessed, the number of peasants that the army could recruit diminished. By the end of the second century bc, soldiers were legally recruited for the first time without regard to property qualifications, even from the urban proletariat. In a sense, this was the beginning of a professional army, in that soldiering was separated from agricultural labor and was recognized as a full-time occupation. This short-term service in the Roman Army, recruited from an underemployed lower class, whether peasant or proletariat, was a significant change. If nothing else, it was the transitional stage between the former peasant army and the full professional army of the early empire.
By professional army, we mean one that is tied by a stable, ongoing relationship to the state and which is paid regularly. It offers a career structure and the opportunity of promotion, of civilian employment after retirement and a pension. The assured regularity of these elements was not a reality until the reign of the Emperor Augustus. Before 27 bc, each Roman Army was recruited by individual commanders for each campaign. Pension rights in the form of land allotments existed, but they depended upon political maneuvering between each general and the state. Even soldiers who enlisted in the long term with successive generals were subject to unpredictable outcomes, and this was one of the main factors in the instability of the army’s behavior during the last century of the Republic.107
It is easy to see how this earlier structure was not conducive to the establishment of a new intelligence arm. There were many amateur elements about it, and no mechanism existed for radical change. When Hannibal invaded Italy in 216 bc, for example, the Romans sent out a large army under two consuls, who held command on alternate days. This is because it was traditionally assumed that one aristocrat, whether he be consul or praetor, was as good as another at commanding troops and fighting battles. It was believed that supreme power should not, if possible, be concentrated in the hands of just one aristocrat. He might win too much glory. The principle of leadership was obviously not dictated by the demands of military tactics, intelligence, strategy, or even skill. The fact that this dual leadership gave Hannibal an advantage did not matter. And in the same way, just discovering that better intelligence gathering might enhance success was not enough to encourage structural changes.108 When Caesar began to choose his lieutenants, not according to their social origin but according to their skill, the process of displacing the noble amateur with the professional began.109 The long civil wars of the last century bc and the quasi-professional army that serviced them began training “professional” personnel at all levels with specific skills, rules of conduct and expectations. It is in this latter army that we begin to see intelligence being taken seriously.
Besides the professionalization of the military, there were other social changes that were tearing at the fabric of the Roman Republic. One of the most symptomatic weaknesses of the senatorial government was its inability to control provincial governors. Military expansion in the late Republic became a search for profit and higher office, and there was little control from the central government. It has been argued that it was this process that stopped the Romans from providing continual administration of the lands they conquered early in the second century bc.110 These provincial magistrates wielded considerable authority, and operated quite a distance from Rome. Given the poor state of communications and the absence of a state-employed supervisory bureaucracy, this minimized the amount of control the central authority could exert over them. Each provincial governor was given the total delegated authority of the Roman state – administrative, judicial, and military. His subordinates were not members of a professional bureaucracy but were his own friends (necessarii), chosen ad hoc. The only limits to the governor’s powers were the short term of office (under two years) and the possibility of being indicted for bribery or extortion by his political enemies when he returned to Rome. Most of the time, even extreme corruption went unpunished. In such a milieu, a centralized intelligence service or an internal security organization would have been abhorrent. No aristocratic family of wealth would have wanted control of such an organization to be put in the hands of a competing family. Aristocratic fears of losing power to a central bureaucracy were justified. The new administrative apparatus of the empire came about by increasing the number of executive magistrates from 25 in 250 bc to 44 after 80 bc. In the first century bc, as part of the same process, the Senate was doubled in size and aristocratic exclusiveness was abolished.
The profits from provincial exploitation and the control of men and money in the province, served as a springboard for rebellion, social change, and eventually revolution in the last century of the Republic. The central government simply could not contain aristocratic competitiveness, because it could not control patterns of acquiring and consuming wealth.111 Competition increased as the rewards for political office and provincial governorship increased. Competition between aristocrats for plebeian votes and for political offices intensified. Although aristocrats had always competed, now the norms and institutions regulating the pattern of competition changed. Competition for political office in the early Republic had been restrained within reasonable bounds, and there was clearly sufficient glory in it to cause them to subordinate their individual interests to the collective good. Not so in the late Republic. By this time, losing an election could mean losing the family fortune and thus inviting social disaster. A group of nobles who had been impoverished in this way attempted a coup d’état in 63 bc.
Cambridge historian Keith Hopkins has explained better than anyone what happens when political, economic, and social activities, which are typically embedded in the family, are taken over by the state. Rome had no executive establishment through which it could control the lifestyles and corruptions of the rich. For such laws to be efficiently executed, there needs to be executive personnel and a dominant body of consensus that condemns the law breakers. Rome had neither. Had these changes affected only education or religion or lifestyle, it would not have mattered much. But they affected the place in society of new institutions and groups, such as the semiprofessional army, the impoverished aristocrats, and very rich equites. What had presumably made Rome strong was its cohesion and reliance upon tradition. What Rome lacked was a set of institutions with enough strength, flexibility, and support to provide innovation, regulate the interaction of the new professional institutions, and win a consensus for the status allocated them.
In short, the process of developing bureaucratic specialization involved the evolution of special roles, norms, and rules that enabled each institution to maintain its autonomy. In Rome, this autonomy was restricted by the continuing power of aristocratic kinship groups. The process of structural differentiation caused conflicts among the new institutions and between them and the ruling elite. The effect that the emergent specialized institutions had on traditional patterns of behavior caused open conflict between those who favored or had interest in traditional authority and those who sought to increase their power by exploiting the emergent new institutions. As long as Roman society was organized on the basis of kinship, locality, and hereditary status, it would be impossible to create or maintain organizations based on achievement, impersonality, and bureaucratic efficiency. When the dominant form of personal interaction is clientship and personal recommendation, then we do not have a modern bureaucracy whose hallmarks are formality and impersonality. Roman bureaucrats often compromised their formal behavior and accommodated themselves to the informal assigned demands of their friends, enemies, and clients. The typical response is what we call corruption.112
The new institutions had no established place within the society, and there was no powerful mechanism within the traditional structure capable of accommodating change on such a scale. There was no consensus as to the place that these institutions should occupy, and the initial reaction of the Senate, that they could be easily assimilated into traditional patterns, was patently ill-informed. Rome failed to establish this consensus during the Republic, and what the following chapters explain is the eventual if partial success in establishing one under the emperors. It was the victorious general, the last of a long succession, who became the emperor who founded the Roman imperial bureaucratic state. Continual wars and political executions had destroyed many bastions of the old order. Augustus discovered that integration could be based on two main foundations. First, gradual reform was legitimized by an ideology of the restoration of tradition. Second, a patrimonial bureaucracy was created that mediated the interests of the emperor, the aristocracy, the taxpayers, and the army. Augustus later completed this process of professionalization and brought to both the political and military facets of the intelligence business an organization and institutionalization that it had previously lacked.
Notes
1. Livy 22.43.10–16. The Voltumus wind is today called the Sirocco.
2. See Appian, bc 4.7.55, where Cornificius sends Laelius out with cavalry on reconnaissance. At Cynocephalae, both parties sent out scouts for ambush and reconnaissance and encountered one another very quickly. Appian, bc 5.3.23 shows Octavian running into an advance guard of horsemen. Appian, BC 5.11.100.14 has Pompey sending out ships to reconnoiter the dockyards of Octavian.
3. Appian, Wars in Spain 16, for the death of Publius and Gnaeus Scipio.
4. Caesar, BG 1.41; 8 miles away in 1.12. On the definition of exploratores, see A. Ezov, “The ‘Missing Dimension’ of C. Julius Caesar,” Historia 45 (1996), pp. 72–9.
5. For scouts from friendly tribes see Caesar, BG 6.10, 6.29.
6. Caesar, BG 1.22. M.A. Richardson, “Julius Caesar’s Use of Intelligence,” MA thesis, Defense Intelligence College, 1984, p. 44.
7. For enemy river-crossings see Caesar, BG 1.12; for the moving of their camp, 1.22.
8. Website: Ibid., 2.17.
9. Website: Ibid., 7.44.
10. Website: Ibid., 8.36.
11. See Fuller, Julius Caesar, p. 317.
12. Caesar, BG 2.8.
13. Plutarch, Sertorius 3. It has been suggested that this was not mere reconnaissance but rather part of a repeated or long-term operation in northern Gaul undertaken at a time when Germans were operating in the area, in 103. There is no further evidence to support this suggestion. See P. Spann, Quintus Sertorius and the Legacy of Sulla (Fayetteville, AK: University of Arkansas Press, 1987), pp. 13–17, who questions why a Gallicized Roman would be used instead of a Romanized Gaul.
14. 212 bc. Frontinus 3.3.2. makes it sound as if Marcellus did the scaling and slaying himself. See rather Livy 25.23ff., Plutarch, Marcellus 18; Polyaenus 8.11, who also all name a Spartan called Damippus rather than Sosistratus as the source of the information.
15. Frontinus 3.3.1; Zonaras 8.6.
16. H.P. Judson, Caesars’s Army (Boston: Ginn, 1888), p. 27. Richardson, “Caesar”, p. 23. See the critical comments of Ezov, “The ‘Missing Dimension’”, pp. 85–93.
17. Dispatches sent to Rome, Caesar, BG 2.35, 4.38.5, 7.90.8; message from Labienus, 2.1.
18. Website: Ibid., 2.1.
19. Website: Ibid., 1.7.
20. 20 B. Afr. 31.
21. 21 B. Afr. 37.
22. BH 28.
23. 23 B. Afr. 35.
24. 24 Speculatores: BC 3.66,67; B. Afr. 12, 31, 35, 37; BH 13, 20, 22,28, 38.
25. Caesar, BG 2.11.
26. Website: Ibid., 5.50.
27. 27 B. Afr. 35.
28. BH 13, A.G. Way translation, Loeb Classical Library edition.
29. Website: Ibid., 20.
30. Caesar, BG 8.8.
31. On the treatment of prisoners of war see M.M. Westington, Atrocities in Roman Warfare (Chicago, IL: University of Chicago Press, 1933), pp. 5–27.
32. Caesar, BG 1.19.
33. Website: Ibid., 5.36.
34. Website: Ibid., 1.19.3; 1.47.4–6; 1.53.5–8.
35. Website: Ibid., 1.50.
36. Website: Ibid., 7.72.
37. Fuller, Julius Caesar, p. 157 calls it “one of the most extraordinary operations recorded in military history.”
38. Caesar, BG 7.18.
39. Website: Ibid., 8.17.
40. Website: Ibid., 8.18; see Anne and Peter Wiseman translation, The Battle for Gaul (London: Chatto & Windus, 1980).
41. Caesar, BG 1.22; 2.17; 5.8; 5.52.
42. Website: Ibid., 3.18; 5.18; 7.44; 7.72; 8.40.
43. Website: Ibid., 7.72.
44. Website: Ibid., 7.44.
45. 45 B. Afr. 35.
46. BH 11.
47. Information from deserters: Appian, BC 2.28, 2.39, 3.63, 3.49, 3.71; B. Afr. 62, 66, 68; BH 6, 20, 34, 35. Information confirmed by local inhabitants: B. Afr. 8.
48. 48 B. Afr. 65, 66.
49. Appian, BC 1.66.
50. Website: Ibid., 1.67.
51. Frontinus 3.13.3.
52. Frontinus 3.13.4. For examples of more sophisticated Greek methods, see R.M. Sheldon, “Tradecraft in Ancient Greece,” Studies in Intelligence 30, 1 (1986), pp. 39–47.
53. Frontinus 3.13.5.
54. 74 bc, Frontinus 3.13.6. Cf. Florus 3.5.15–16; Orosius 6.2.14.
55. 43 bc, Frontinus 3.13.7. Cf. Dio Cassius 46.36.
56. 43 bc, Frontinus 3.13.8. Cf. Pliny, HN 10.37.
57. This presumes that the same pigeons were used over and over again, which most scholars think unlikely. The pigeons would have to be returned in crates if the logistics of the story are correct, but how to return the crates if they could not get the messages through any other way? On the history of the use and training of carrier pigeons, see H. Fischl, Die Brieftaube in Altertum und im Mittelalter (Schweinfurt, 1909), and M. Sabbagh, La Colombe messagère plus rapide que la mouse, trans. from the Arabic by A.I. Silvestre de Sacy (Paris, 1805).
58. Caesar, BG 5.48 trans. Wisemans, in Battle for Gaul. Rice Holmes, Conquest of Gaul, p. 730, has argued that the message was written in Greek characters. Yet two passages in the Gallic Commentaries show that Caesar knew that Greek was commonly used by some Gauls (BG 1.29, 6.14). Classical Weekly 31 (October 1937–May 1938), p. 90, points out that “mere transliteration into Greek letters would have afforded Caesar’s message no secrecy if it were intercepted by the enemy.” This seems to be the stronger argument. The grammarian Valerius Probus wrote a treatise that has not survived on the ciphers used by Julius Caesar. See D. Kahn, The Codebreakers (New York: Scribner’s, 1996), p. 84.
59. Suetonius, Div. Jul. 56.6, explains that, to decipher these cryptograms, each of the letters in Caesar’s ciphertext would be replaced with the one that occurs three characters ahead in the alphabet (for example, A stands for D). For a broader examination of this system, see E.C. Reinke’s “Classical Cryptography,” CJ 50 (October 1962–May 1963), pp. 113–21. Augustus’s improvements are mentioned in Suetonius, Augustus 88. For a later period, Aulus Gellius, Attic Nights 17.9 refers to ciphers that may very well be more complex than either Caesar’s or Augustus’s, but the literature does not give us enough information to make that judgment. For the possible influence of classical sources upon Renaissance writers, see Wilhelm Suess, “Über antike Geheimschriftmethoden und ihr Nachleben,” Philologus 78 (June 1922), pp. 142–75.
60. Appian, BC 3.65, 67.
61. Website: Ibid., 3.43.
62. Website: Ibid., 3.72.
63. Dvornik, Origins of Intelligence Services, p. 86. See Caesar, BC 3.100–101.
64. Livy 40.56 gives the last evidence of a Macedonian post when he reports how Perseus, hiding in Thrace, received the news of his father’s death from Macedonia. See Dvornik, Origins of Intelligence Services, p. 87.
65. Appian, BC 3.11.
66. See Dvornik, Origins of Intelligence Services, p. 87 citing Livy 40.56 on how Perseus, hiding in Thrace, received news of his father’s death from Macedonia.
67. Josephus, Jewish War 3. 76–78; Vegetius 1.14, who notes that failing to construct a proper camp left Roman forces open to surprise attacks by enemy cavalry. Cf. Webster, Roman Imperial Army, p. 30, who notes that building nightly camps set the Romans apart from all other forces in the ancient world.
68. Dio Cassius 9, frag. 43.
69. Dio Cassius 21 (Zonaras 9.3).
70. Vegetius 3.3.
71. Vegetius 3.3. Cf. W. E. Messer, “Mutiny in the Roman Army. The Republic,” CP 15 (1920), pp. 149–75. See the mutiny against Augustus at Brundisium in 30 bc and the frontier mutiny in ad 14.
72. Livy 7.38–39.
73. Vegetius 3.3. See, for example, the mutiny at Placentia, where the ringleaders are put to death.
74. Vegetius 3.26.
75. 79–72 bc, Frontinus 1.1.12, Charles E. Bennett translation, Loeb Classical Library edition; cf. Valerius Maximus 7.4.5.
76. Frontinus 1.1.13, Charles E. Bennett translation, Loeb Classical Library edition; Plutarch, Demetrius 28 tells the same story of Antigonus and Demetrius.
77. 104 bc, Frontinus 1.2.66. For a similar example used at sea, compare Polyaenus 4.7.2.
78. 75 bc, Frontinus 2.7.5.
79. For definitions, see Department of the Army, FM 5–30, Combat Intelligence (Washington, DC: GPO, 1971), p. 8 – 1.
80. Caesar, BG 5.50–51.
81. Website: Ibid., 7.60.
82. Dodge, Art of War, p. 206.
83. Caesar, BG 5.57.
84. Website: Ibid., 6.7. On Labienus’s skill in deceiving the enemy, see F.F. Abbot, “Titus Labienus,” CJ 13 (1917), pp. 4–13.
85. Caesar, BG 3.18.
86. Dio 42.17.2, Earnest Cary translation, Loeb Classical Library edition.
87. Website: Ibid., 50.2.2.
88. Appian, bc 3.43.
89. Cicero, Ad. Fam. 9.16.4.
90. J.H. Collins, “Propaganda, Ethics and Psychological Assumtions in Caesar’s Writings”, PhD dissertation, Frankfurt, 1952, pp. 109–15. An account may have been given by Caesar in the lost section of the BC that originally followed 3.8.
91. Dio Cassius 43.5.1–2, Earnest Cary translation, Loeb Classical Library edition. B.Afr. 32. Octavian tried subverting Antony’s army in 44 bc with pamphlets, Appian, BC 3.44; the Caesarians did the same against Brutus before the second Battle of Philippi, Dio Cassius 47.48.1; when Antony had such leaflets shot into Octavian’s camp outside Alexandria in 30 bc Octavian read them to his soldiers himself, Dio Cassius 41.10.2–3. See W.V. Harris, Ancient Literacy (Cambridge, MA: Harvard University Press, 1989), p. 253.
92. Harris, Ancient Literacy, p. 253.
93. Dio Cassius 50.9.4.
94. Suetonius, Div. Jul. 59.
95. Appian, BC 3.71.
96. 96 B. Afr. 44–46.
97. Caesar did not hesitate to use the charge of cruelty against Pompey in the BC. See Collins, Propaganda, pp. 64–6.
98. Fuller, Caesar, p. 321.
99. Plutarch, Caesar 17, Bernadotte Perrin translation, Loeb Classical Library.
100. Suet., Div. Jul. 1.57.
101. Plutarch, Div. Jul. 32. On the history of postal services, see Dvornik, Origins of Intelligence Services.
102. See B. Campbell, “Teach Yourself how to be a General”, Journal of Roman Studies 65 (1975), p. 325 on the training of army officers.
103. Grant, Army of the Caesars (New York: Scribner’s, 1974), p. xxxiii.
104. Cicero, Acad. 2.1.2, H. Rackham translation, Loeb Classical Library.
105. Sallust, Jugurtha 85.12, J.C. Rolfe translation, Loeb Classical Library; Cicero, ad Fam. 9.25.1, who mentions Pyrrhus, king of Epirus, and his minister, Cineas, who both wrote treatises on military affairs.
106. K. Hopkins, “Structural Differentiation in Rome (200–31 bc): The Genesis of an Historical Bureaucratic Society,” in I.M. Lewis (ed.), History and Social Anthropology (London: Tavistock, 1968), pp. 63–79.
107. Website: Ibid., p. 65.
108. Website: Ibid., p. 72.
109. Suetonius, Julius Caesar 65.
110. Hopkins, “Structural Differentiation,” p. 68.
111. There were sumptuary laws, and senators were forbidden to participate in large-scale maritime trade. For a discussion of these and other limits, see Hopkins, “Structural Differentiation,” p. 69.
112. Website: Ibid., p. 73.