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

ACTA SENATUS Official record of the proceedings of the Roman Senate, kept in the Tabularium.

AFRICA The Roman province of Africa occupied today’s Tunisia in North Africa. Gnaeus Calpurnius Piso was governor there in 3 B.C. Piso’s eldest son, Gnaeus Piso, was later also governor of Africa, under the emperor Caligula.

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

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. The troops of the German Guard were auxiliaries.

BAETICA The Roman province of Farther Spain, roughly corresponding with modern-day Andalucia, where Seneca, his father, and his brothers were born and where Gnaeus Calpurnius Piso was governor for a time.

BASILICA Roman meeting hall, used for court sessions and other public business. Once the Roman Empire officially became Christian, churches followed the basilica design.

BATAVIAN Native of Batavia, a former German kingdom subjugated by Julius Caesar. The Batavian lands today form part of the Netherlands.

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. By the third century A.D. the unit had become the emperor’s household cavalry unit.

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

CAMPAIGNING SEASON Traditionally, in the imperial era, early March to October 19, when legions conducted military campaigns, after which they went into winter quarters. The October 19 date originally marked the date of the ancient Festival of the October Horse, when Rome’s soldiers came home from the army to conduct the harvest. The terms “seasoned campaigner” and “seasoned soldier” derive from Roman times, denoting soldiers who have served one or more campaigning seasons in the army.

CASTRA PRAETORIA Massive castlelike Praetorian barracks at Rome, built early in the first century by its then commander Sejanus, in the city’s northeastern fourth Precinct. Torn down by the emperor Constantine in the fourth century after he abolished the Praetorian Guard.

CENTURION Legion, Praetorian/City Guard and Marines officer, fifty-nine to an imperial legion, in eleven grades. Equivalent to first lieutenant and captain. Enlisted man promoted from ranks, although there were some Equestrian Order centurions in 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). A legion’s most senior centurion.

CITY GUARD A military unit made up of former slaves that served as the police force and fire brigade of Rome and manned the city gates. Comprised four cohorts of fifteen hundred men each. The City Guard and the Night Watch both reported to the city prefect of Rome. In early imperial times, one cohort of Rome’s City Guard was permanently stationed at the Gallic city of Lugdunensis (Lyon, France), to guard the official mint there, and another was stationed for a time at west coast ports in Italy.

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, forty-two; in the empire the minimum age was thirty-seven, except for members of the imperial family.

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

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

CURIA Senate House at Rome.

CURILE CHAIRS The seats of the two current consuls in the Senate House.

CURSUS PUBLICUS VELOX Literally, “the state’s very fast runner.” Imperial Rome’s courier service. Founded by the emperor Augustus with runners on foot; soon expanded to wheeled vehicles and mounted couriers. Horses were changed at way stations, checked by inspectors, every 6 to 10 miles. Covered up to 170 miles per day. Compare with the nineteenth-century U.S. Pony Express, which covered 180 miles per day. It was a capital offense to interfere with cursus publicus couriers or their load. Cursus publicuscarriages only carried passengers who had the personal permission of the emperor to ride in them.

DECIMATION Literally, to reduce by a tenth. Legions were punished for mutiny or cowardice by one man in ten being clubbed to death by their comrades after drawing lots. The 9th Legion, later the 9th Hispana, was the only legion on record to be decimated twice.

DECUMAN GATE The main gate of a legion camp and of Rome’s Castra Praetoria. Faced away from the enemy.

DECURION Legion cavalry officer. Equivalent of a second lieutenant. Four to each legion cavalry squadron. Also, 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 imperial era served mandatory six-month legion cadetship as junior tribune at age eighteen or nineteen.

EVOCATI In the imperial era, militia corps of retired legion veterans, serving behind their old standards in emergencies. Controlled by their provincial governor.

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. Dictators and some emperors used twenty-four lictors.

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. There were several forums at Rome.

FORUM ROMANUM Original and main forum at Rome.

FREEDMAN A former slave, officially granted freedom.

FRIGATE Liburnian; light, fast warship. Its length was 108 feet; beam, 12 feet. It had a crew of 144 rowers, 10 to 15 sailors, and 40 marines.

FURLOUGH FEES In camp, one legionary in four could take leave by paying a set fee to his centurion. The state took 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 emperor; handpicked German auxiliaries. Comprised 10 cohorts, each of 480 men. Four cohorts were based at Rome at any one time, at the Palatium, with the remainder stationed in towns outside Rome on rotation.

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 and discipline.

GLADIUS Roman legionary sword, twenty inches long, double-edged, with a pointed end. Known as the Spanish sword because the best were made in Spain.

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 “Armed” front-line 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, 5,185 enlisted men and 72 officers, including own cavalry unit of 124 officers and men. At the beginning of the first century there were 28 legions. At the end of the war of succession, A.D. 69, there were 32 legions. By A.D. 102, 30; and 33 in A.D. 233.

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

LICTORS Unarmed attendants of senior Roman officials, carrying their fasces.

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

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

MANTLET Wooden shed, on wheels, used in siege works by the Roman army.

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

MARINE Soldier serving in 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 first Roman soldier over an enemy city wall.

NAVY Prior to the emperor Augustus, Rome relied on its provinces and allies to provide its battle fleets. The imperial Roman navy had 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 on the Crimean Peninsula to cover the Black and Azov seas.

NIGHT WATCH Nighttime police force and fire brigade at Rome; established by Augustus. Made up of ex-slaves. In seven cohorts of a thousand men each, stationed throughout the city. Reported to the city prefect.

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

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

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 vast new palace, the Domus Augustana, which incorporated Augustus’s old residence, known as the Old Palatium, would serve as the Palatium of many later emperors.

PALUDAMENTUM 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 Roman magistrate and major general. Could command legions and armies. Entitled to five lictors.

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

PRAETORIAN GUARD Elite unit founded in the republic to guard the praetors of Rome. Reformed by Mark Antony and made his bodyguard. Became an elite military police force in imperial times. Recruited exclusively in Italy, Praetorians were paid more than legionaries, served less time (sixteen years from late in the reign of Augustus), and received a larger retirement bonus (20,000 sesterces, as opposed to the legionary’s 12,000). For centuries the Praetorian Guard was, along with the German Guard, City Guard, and Night Watch, the only military unit stationed in Italy.

PRAETORIUM Headquarters in a Roman military camp.

PREFECT Commander of auxiliary units, Praetorian Guard, City Guard, and naval fleets. Usually 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. In imperial era had an annual salary of 60,000 to 100,000 sesterces.

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

QUADRIGA Roman chariot drawn by four horses. A ceremonial golden quadriga was used in Triumph parades.

QUAESTOR “Investigator.” Lowest-ranking Roman magistrate. Assistant to consul and provincial governors. Served as quartermaster in republican field armies. In imperial times responsible for treasury matters, military recruiting, and special commissions.

RANK AND FILE Enlisted men of a legion.

ROSTRA Speakers’ platforms in the Forum at Rome.

SARDONYCHIS Emperor’s personal seal, introduced by Augustus in 27 B.C., when he was granted his title. Used by most subsequent emperors. Bore 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, and probably in emulation of Julius Caesar’s seal, which bore the Caesar family’s emblem, the elephant. 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 last thing added to outgoing letters.

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.

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 thirty in imperial times. In Caesar’s time, some 350 to 400 members. 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 one year, by lot, from its members. With the rank of proconsul, the senatorial governor had capital punishment power but couldn’t wear a uniform or a sword, or levy troops. His province had a 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 per year.

SIGNIFER Literally, a signaler; the standard-bearer of legion subunits and Praetorian Guard cohorts.

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

TABULARIUM Official archives at Rome. Built in 78 B.C., on the northern side of the Forum Romanum, at the foot of the Capitoline Mount. The building was incorporated into the Senate Palace that stands on the site today.

TESSERA A small wax sheet on which was inscribed the legion 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.

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

TREASURY OF SATURN Rome’s main treasury, in the basement of the Temple of Saturn. Managed by former praetors with a staff of some thirty-six clerks in early imperial times. Separate and distinct from the military treasury, which was incorporated into the Palatium.

TRIBUNAL Reviewing stand in legion camp, built in front of tribunes’ quarters. In a legion marching camp, it was built from “bricks” of turf. From here the commander addressed assemblies of his troops, and his adjutant announced daily orders each morning.

TRIBUNE Legion, Praetorian Guard, and City Guard officer. Six of equal rank in republican legions shared command. In imperial legions, a “thin stripe” junior tribune was officer cadet serving a mandatory six months; five to a legion. One “broad stripe” senior tribune (so-called Military Tribune) per legion was a full colonel and legion second-in-command. From the reign of Claudius, for promotion purposes, twenty-five military tribunes were appointed annually, but not all were given legion or Guard posts. Ten tribunes of the plebeians also were elected at Rome, sitting in the Senate; their republican power of veto over Senate votes was absorbed by the emperor.

TRIREME Midsize Roman warship with three banks of oars. The most common ship in Roman fleets.

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

TRIUMPHAL DECORATIONS A crimson cloak, crown of bay leaves, laurel branch, and statue in the Forum for generals celebrating a Triumph; and in lieu of 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 and at Rome. 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 tribune commanding the Praetorian Guard’s duty cohort at Rome 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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