ACTA DIURNIA Rome’s Daily News, world’s first newspaper. Handwritten daily by the Palatium at Rome and sent around the empire. Founded by Julius Caesar in 59 B.C. when he was consul for the first time.

AQUILIFER Standard-bearer who carried the aquila, the legion’s eagle. Eagle-bearer.

AUXILIARY Noncitizen serving in Roman army. Light infantry and cavalry. Recruited throughout empire. In imperial times served twenty-five years. Paid less than legionary. From the first century A.D., granted Roman citizenship on discharge. Commanded by prefects.

BATAVIAN HORSE Elite auxiliary cavalry unit of Roman army. Recruited in present-day Holland. Its troopers were famous for being able to swim rivers with their horses in full equipment. Initially, Batavians formed the core of Julius Caesar’s personal bodyguard of three hundred “Germans.” By the third century A.D., the Batavian Horse regiment was the emperor’s household cavalry unit.

BATTLESHIP Roman warship of Deceres class; 572 oarsmen, 30 sailors, 250 marines.

BOLT Large metal-tipped arrow fired by archers and scorpio catapults.

CAMP PREFECT Campus praefectus. Imperial legion officer, third in command after commander and senior tribune. Promoted from centurion. Quartermaster, commander of major legion detachments. Took over the role filled by quaestors in republican armies.

CAMPAIGNING SEASON Traditionally, early March to the Festival of the October Horse on October 19, when legions conducted military campaigns, after which they went into winter quarters. The terms “seasoned campaigner” and “seasoned soldier” derive from this.

CENTURION Legion, Praetorian/City Guard, and Marines officer, sixty to a republican legion, in eleven grades. Equivalent to first lieutenant and captain. Enlisted man promoted from ranks, although there were some Equestrian Order centurions in the late republic/early empire.

CENTURY Legion subunit made up of ten squads. In republican times, of a hundred men. In imperial times, of eighty men. Commanded by a centurion.

CHIEF CENTURION Primus pilus (first spear). Legion’s most senior centurion.

CIVIC CROWN Crown of oak leaves, military bravery award for saving the life of a Roman citizen in battle. Rarely awarded, highly prized. Julius Caesar was a recipient.

COHORT Battalion. Ten to a legion. In Caesar’s time, of 600 men. In imperial times, cohorts 10 through 2 had 480 men, the senior first cohort, 800.


CONQUISITOR Roman army recruiting officer.

CONSUL Highest official at Rome; president of Senate. Two held office annually. Also commanded Roman armies, with equivalent rank of lieutenant general. The minimum age in the Republic was forty-two; in the imperial era the minimum age was thirty-seven, except for members of imperial family.

CONTUBERNIUM Legion subunit; the squad. In the Republic, of ten men; in the empire, of eight men.

CRUISER Midsize warship, including bireme, trireme, and quinquereme. The latter was 120 feet long, with a beam of 17 feet, a crew of 270 oarsmen at 3 banks of oars, 30 sailors, and 160 marines.

CURSUS PUBLICUS “The state’s very fast runner.” Imperial Rome’s courier service. Founded by emperor Augustus with runners on foot; soon expanded to wheeled vehicles and mounted couriers. Horses changed at way stations, checked by inspectors every 6 to 10 miles. Covered up to 170 miles per day. It was a capital offense to interfere with cursus publicus couriers or their load.

DECIMATION Literally, to reduce by a tenth. Legions punished for mutiny or cowardice by one man in ten being clubbed to death by their comrades after drawing lots. Ordered to be carried out by both Caesar and Antony on units under their command. The 9th Legion, later the 9th Hispana, was the only legion on record to be decimated twice, the second time being in the first century during the reign of Tiberius.

DECUMAN GATE The main gate of legion camp, it faced away from the enemy.

DECURION Legion cavalry officer. Equivalent of a second lieutenant. Four to each legion cavalry squadron. Also, a senior elected civil official of a Roman town.

DICTATOR Supreme and sole chief of Rome. An ancient appointment, made by the Senate in emergencies, intended to last a maximum of six months. Sulla used the position to make himself ruler of the Roman Republic. Julius Caesar appropriated the title, with several temporary appointments, before becoming Dictator for life in February 44 B.C.

EAGLE The aquila, sacred standard of a legion; originally silver, later gold.

EQUESTRIAN Member of Roman order of knighthood. Qualified for posts as tribune, prefect, procurator, and Senate membership. Required net worth of 400,000 sesterces. In the imperial era served a mandatory six-month legion cadetship as junior tribune at age eighteen or nineteen.

EVOCATI In republican times, the general term for legion veterans. In the imperial era, a militia corps of retired legion veterans serving behind their old standards in emergencies and controlled by their provincial governor. Cassius Dio described them as “the recalled,” because they were from time to time recalled to military duty.

FASCES Symbol of Roman magistrate’s power to punish and execute, an ax head protruding from a bundle of wooden rods. Carried by lictors. Denoted rank: quaestors had one, legates five, praetors six, consuls and most emperors twelve, dictator and some emperors twenty-four.

FIRST-RANK CENTURIONS Primi ordines; a legion’s six most senior centurions.

FORUM Open space, usually rectangular, in all Roman cities and towns where law courts, meeting halls, temples, markets, and speakers’ platforms were located.

FREEDMAN Former slave, officially granted freedom.

FRIGATE Liburnan; light, fast warship. Length, 108 feet; beam, 12 feet; crew, 144 rowers, ten to fifteen sailors, and forty marines.

FURLOUGH FEES In camp, one legionary in four could take leave by paying a set fee to his centurion. The state took the responsibility for paying centurions these fees in A.D. 69.

GEMINA LEGION “Twin” legion formed by merger of two existing legions.

GERMAN GUARD Elite bodyguard unit of a Roman emperor, made up of handpicked German auxiliaries. Instituted by Augustus.

GLADIATORS Professional fighters used in public shows throughout the empire. Usually slaves. Gladiatorial contests originated as funeral rites. Sometimes used as soldiers in civil wars, but usually without success, as they lacked unit training or discipline.

GLADIUS Roman legionary sword, twenty inches long, double edged, with a pointed end.

IMPERATOR Title. Literally, chief or master. Highest honor for a general. Became reserved for emperors after their armies’ victories. Title “emperor” grew from imperator.

IMPERIAL Relating to the period of Roman history from 27 B.C. to the fall of the empire.

IMPERIAL PROVINCE In the imperial era, an “armed” frontline province bordering unfriendly states, administered by the Palatium. Garrisoned by at least two legions plus auxiliaries. Governed by a propraetor (lieutenant general), a former consul whose appointment, by the emperor, was open-ended. A propraetor commanded all troops in his province, could wear a sword and uniform and levy recruits, and had capital punishment power.

JUVENA COLLEGA Young Men’s Association. Ancient guild for sons of Roman nobility in Italy. Fostered by Augustus. Boys joined at age seventeen. Learned horsemanship, weapons skills, manliness, etc., as a prelude to entering the army at eighteen as officer cadets.

LEGION Regiment. Main operational unit of the Roman army. From legio (levy, or draft). In 10 cohorts. Republican legion nominal strength, 6,000 men; imperial, 5,246 officers and men, including own cavalry unit of 124 officers and men. At the beginning of the first century A.D. there were 28 legions; by A.D. 102, 30; and in A.D. 233, 33.

LEGIONARY Soldier of a legion. Mostly a draftee. A Roman citizen (with very rare exceptions). Most recruited outside Italy in the imperial era. Republican military age, seventeen to forty-six, served sixteen years; imperial, average age twenty, served twenty years from late in Augustus’s reign.

LICTORS Unarmed attendants of Roman magistrates, carrying their fasces.

LUSTRATION The Lustration Exercise, religious ceremony performed by legions in March. Standards were purified with perfumes and garlands prior to each new campaign.

MANIPLE Company. Legion subunit, of 200 men in the republic, 160 in imperial times. Three to a cohort.

MANTLET Wooden shed, on wheels, used in siege works.

MARCHING CAMP Fortified camp built by legions at the end of every day’s march.

MARINE Soldier with the Roman navy. Freedman. Served twenty-six years, paid less than an auxiliary. Commanded by centurions. Organized by cohorts; unit titles unknown.

MURAL CROWN Crown of gold awarded to the first Roman soldier over an enemy city wall.

NAVY In republican times Rome relied on her allies to provide ships and men to act as Rome’s navy. In imperial times Rome introduced her own navy, with two battle fleets: the Tyrrhenian Fleet, based at Micenum, with a squadron also at Fréjus in southern France; and the Adriatic Fleet, at Ravenna. Other, smaller fleets were the Classis Britannica, at Boulogne; the Classis Germanica, on the Rhine; the Classis Moesica, on the Lower Danube; the Classis Pannonica, on the Upper Danube, and the Classis Pontica, with part based in Pontus and forty vessels based at Kersh to cover the Black and Azov Seas.

OPTIO Sergeant major. Deputy to centurion and decurion. Unit records and training officer. One to a century, four to legion cavalry units.

ORBIS The ring, the Roman legion’s circular formation of last resort.

OVATION Lesser form of a Triumph. Celebrant rode in horseback through Rome.

PALATIUM Origin of the word “palace.” Residence and military headquarters of emperors at Rome. First established by Augustus on Palatine Hill, from which its name derived. All emperors’ headquarters were thereafter called the Palatium, even when new palaces were built by other emperors, including Tiberius, Caligula, Nero, and Domitian. Domitian’s new palace, the Domus Augustana, served as the Palatium of many later emperors. Augustus’s original, absorbed into Domitian’s palace, had become known as the Old Palatium.

PALUDAMENTUM Roman general’s cloak. Scarlet in republican times. In imperial times, legion commanders wore a scarlet cloak; commanders in chief, a purple cloak.

PILUM A Roman legionary’s javelin. Metal-tipped, weighted end, six to seven feet long.

PRAETOR Senior magistrate and major general. Sixteen appointed annually once Caesar came to power. Could command legions and armies.

PRAETORIAN GATE Gate of a legion camp that faced the enemy.

PRAETORIAN GUARD Elite unit founded in Republic to guard Rome. Re-formed by Mark Antony immediately following the murder of Caesar in 44 B.C. with six thousand recently retired legion veterans. Elite imperial military police force under the emperors.

PRAETORIUM Headquarters in a legion camp.

PREFECT Commander of auxiliary units, Praetorian Guard, City Guard, Night Watch, and naval fleets. A citizen of Equestrian Order status. Prefects governed Egypt and, between A.D. 6 and 41, Judea.

PROCONSUL Literally, “as good as a consul.” See SENATORIAL PROVINCE.

PROCURATOR Provincial official of Equestrian Order rank, deputy of governor, superior to prefect. Financial administrator and tax gatherer. Sometimes governed small provinces and subprovinces (e.g., Macedonia and Judea). Had capital punishment power. Annual salary, 60,000 to 100,000 sesterces.

PROPRAETOR Literally, “as good as a praetor.” See IMPERIAL PROVINCE.

QUADRIGA A Roman chariot drawn by four horses. A golden quadriga was used in Triumphs.

QUAESTOR Literally, “investigator.” Most junior Roman magistrate, entitled to one lictor. One assisted each consul at Rome on treasury matters; several others appointed to assist provincial governors on matters including finance, military recruiting, etc. Appointment as a quaestor meant immediate entry into the Senate once a man had served out his appointment. Caesar appointed twenty annually once he was in power. In his time, a provincial governor’s quaestor also served as his chief of staff and quartermaster, with the equivalent modern-day rank of brigadier general, and in this capacity a quaestor could lead legions or armies. Among Caesar’s quaestors in Gaul were young Crassus and Mark Antony.

RANK AND FILE Enlisted soldiers of a legion.

ROSTRA Speakers’ place in the Forum at Rome.

SATURNALIA Festival of Saturn. Originally on December 17, extended to four days, then five, then seven. Slaves could dress like their masters, dice playing was legal, and patrons gave their clients gifts. Origin of Christian Christmas festival and of Christmas gift-giving.

SCORPION Scorpio, quick-firing artillery piece using metal-tipped bolts. Each legion was equipped with fifty of them, plus ten heavy stone-throwing catapults.

SEAL Every Roman of Equestrian Order or Senatorial rank wore a gold signet ring on his left hand. The ring bore his personal seal, which was affixed to all his documents and correspondence. Pompey the Great’s seal was of a lion with a sword in one paw. Caesar’s family seal was the elephant, but once he was Dictator his seal depicted the goddess Venus, from whom Caesar claimed to be descended, wearing helmet and armor. Augustus’s seal, called the Sardonychis and introduced in 27 B.C., was used by most subsequent emperors. It bore an image of Augustus cut by the artisan Dioscurides. For three years prior, Augustus’s seal carried the image of a sphinx, celebrating his victory in Egypt over Antony and Cleopatra. The sphinx was briefly replaced, according to Suetonius, by the head of Alexander the Great. The Sardonychis seal was possibly named for the superior quality wax used, resembling onyx. Also: the Palatium’s outbound correspondence department, so called because the Sardonychis seal was the last thing added to outgoing letters.

SECOND ENLISTMENT MEN Legionaries who voluntarily served another sixteen- or twenty-year enlistment with their legion when their first enlistment expired.

SEGMENTIA LORICA Segmented metal armor adopted by the men of Rome’s legions in the first century A.D. to replace iron mail armor.

SENATE Rome’s most powerful elected body. Members, needing a net worth of 1 million sesterces, qualified for legion commands, praetorships, and consulships. Minimum age 30 in imperial times. In Caesar’s time, some 350 to 400 members, increased by him to 900. At the start of the reign of Augustus, 1,000 members; he subsequently limited it to 600 members.

SENATORIAL PROVINCE In the imperial era, a province with a governor appointed by the Senate for a year, by lot, from its members. With the rank of proconsul (lieutenant general) the governor had capital punishment power but couldn’t wear a uniform or sword or levy troops. Garrison of auxiliaries (except in Africa, where one legion was stationed). Asia and Africa were the most highly prized, best-paid appointments—up to 400,000 sesterces a year.

SIGNIFER Literally, a signaler; the standard-bearer of legion subunits.

SPATHA Roman cavalry sword. It had a round end, and was longer than the gladius.

TESSERA A small wax sheet on which was inscribed the legion’s watchword for the day.

TESSERARIUS Legion guard/orderly sergeant. Distributed the tessera to his men.

TESTUDO “Tortoise” formation. Legionaries locked shields over their heads and at their sides.

THIRD ENLISTMENT MEN Legionaries voluntarily serving a third enlistment.

TORQUE Neck chain of twisted gold. Among the Roman army’s highest bravery awards.

TRIBUNAL Reviewing stand in a legion camp; built in front of tribunes’ quarters.

TRIBUNE (MILITARY) Legion, Praetorian Guard, and City Guard officer. Six of equal rank in republican legions shared command. In imperial legion, a “thin stripe” junior tribune was an officer-cadet serving a mandatory six months; five to a legion. One “broad stripe” senior tribune (a so-called military tribune) per legion was a full colonel and legion second in command. Senior tribunes commanded Praetorian Guard and City Guard cohorts. From the reign of Claudius, for promotion purposes, twenty-five senior tribunes were appointed annually, but not all were given legion or Praetorian posts.

TRIBUNE OF THE PLEBEIANS Ten Tribunes of the Plebeians were elected at Rome, sitting in the Senate. In the Republic they had the power of veto over Senate votes. This power was absorbed by the emperor in imperial times.

TRIUMPH Parade through Rome in a gold quadriga by a victorious general, followed by his soldiers, prisoners, and spoils. He also received T.D.s and a large cash prize. Initially granted by the Senate, later by emperors, and usually only to generals of consular rank.

TRIUMPHAL DECORATIONS (T.D.s) A crimson cloak, crown of bay leaves, laurel branch, and statue in the Forum for generals celebrating a Triumph.

TRIUMPHATOR Roman general celebrating a Triumph.

TRIUMVIRS Members of the 43-33 B.C. Board of Three for the Ordering of State—Octavian, Antony, and Lepidus. Prior to that, unofficially, Caesar, Pompey, and Crassus.

TUNICA PALMATA The palm tunic. A tunic embroidered with a palm frond design worn by generals celebrating a Triumph.

VEXILLUM Square cloth banner of auxiliary units and legion detachments.

WATCH Time in Roman military camps was divided into watches of three hours, at the end of which sentries changed, on a trumpet call. The officer of the watch was a tribune.

WATCHWORD Password in a Roman military camp. Daily, just prior to sunset, the tribune of the watch presented the most senior officer in camp with a register of the number of men fit for duty, and in return was given the watchword for the next twenty-four hours. This was distributed to the sentries by the guard cohort’s tesserarii. In imperial times, the watch tribune of the Praetorian Guard obtained the guard’s watchword from the emperor.

WINTER CAMP A permanent base where a legion usually spent October to March.

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