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— CH. 1 · INTRODUCTION —

Campaign history of the Roman military

17 min listen · Ch. 1 of 8
8 sections
  • The campaign history of the Roman military begins with a small tribal village on a hilltop in Italy and ends, over a thousand years later, with an empire that covered much of Southern Europe, the Near East, and North Africa. What holds that span together is not a single dynasty or ideology, but something more stubborn: a military machine that could absorb catastrophic defeat after catastrophic defeat and keep coming back.

    At the Battle of Cannae, Hannibal handed Rome one of the worst defeats in ancient warfare. At the Battle of Carrhae, the Parthians slaughtered a Roman army in the desert. At the Battle of Teutoburg Forest, Arminius destroyed three legions nearly to the last man. Each time, Rome sent another army. Each time, the enemy who had won the battle eventually lost the war.

    The historian Livy, writing in the first century BC, framed Rome's earliest campaigns as legend as much as history, openly admitting that events before the city was founded were "handed down more as pleasing poetic fictions than as reliable records." Yet by the middle republic, the record becomes dense with battles, treaties, sieges, and the names of enemies who underestimated Rome's capacity for obstinate persistence. How did a hilltop village become a Mediterranean superpower? What patterns of warfare made that transformation possible, and what eventually undid it? Those are the questions this documentary will follow.

  • Livy lists seven kings of early Rome, spanning from the city's founding to roughly 509 BC, but he is candid that the first four, Romulus, Numa, Tullus Hostilius, and Ancus Marcius, may be apocryphal. What fragmentary accounts exist describe a city fighting for its life against neighbours on every side.

    The first campaigns in this legendary account are wars against the Latin cities and the Sabines. According to Livy, the Latin village of Caenina invaded Roman territory in response to the notorious abduction of the Sabine women, but was routed and captured. The Sabines themselves later attacked Rome, briefly seizing the citadel, before being persuaded to conclude a treaty under which they became Roman citizens.

    By the time Tarquinius Priscus took the throne, traditionally dated to 616 BC, the military record becomes marginally more concrete. The Fasti Triumphales, the official Roman list of triumphs, records that Tarquinius celebrated a victory over the Sabines on the 13th of September, 585 BC, having doubled the numbers of cavalry to win the war. He then subdued a string of Latin cities: Corniculum, old Ficulea, Cameria, Crustumerium, Ameriola, Medullia, and Nomentum.

    Servius Tullius, who ruled from 578 to 535 BC, warred against Veii and the Etruscans and, according to the Fasti, celebrated three triumphs over them, including on the 25th of November, 571 BC and the 25th of May, 567 BC. His successor, Tarquinius Superbus, was Rome's seventh and final king. He unified Roman and Latin troops into combined military units, attacked the Volsci, and erected the Temple of Jupiter Optimus Maximus with the spoils from the wealthy town of Suessa Pometia. His reign ended not in battle but in political revolution: his army, camped outside the town of Ardea during a siege, welcomed Lucius Junius Brutus as their new leader and expelled the king's sons.

  • After the kings were gone, Rome in the early Republic faced what the historian Florus described as a problem of geography: "at whatever gate they went out, were sure to meet a foe." The city fought Etruscans, Sabines, Aequi, Volsci, and a dozen Latin towns, winning some and losing others, gradually extending the radius of territory it could call its own.

    The Battle of Lake Regillus in 496 BC saw Rome defeat the Lavinii and Tusculi. The Battle of the Cremera in 477 BC went the other way, a defeat at the hands of the Veientes. The long Siege of Veii ended in 396 BC with Roman victory. These were local wars, known mainly to the people fighting them. Rome's affairs, the source notes, "were only just coming to the attention of the Greeks, the dominant cultural force at the time."

    All of that changed around 390 BC. Several Gallic tribes had been expanding southward through Italy, and a particularly warlike group, the Senones, attacked the Etruscan town of Clusium, well within Rome's sphere of concern. The Clusians asked Rome for help. Almost inadvertently, Rome found itself facing the Senones directly at the Battle of the Allia. The Gauls, under their chieftain Brennus, defeated a Roman force of around 15,000 troops and then pursued the survivors back to Rome itself, partially sacking the city.

    What happened next became Roman legend. The exiled dictator Marcus Furius Camillus gathered the scattered survivors and marched to Rome. According to tradition, Brennus had weighted the scales when measuring the gold ransom for the city, prompting the famous cry "Vae Victis!" (Woe to the losers). Camillus reportedly answered that the homeland is released with iron, not with gold, then attacked the Gauls and drove them out. His fellow citizens hailed him as alter Romulus, the second founder of Rome. Whether or not the details are historical, the encounter shaped Roman strategic anxiety for generations. Intermittent Roman-Gallic conflict in Italy continued for more than two centuries, ending only with the final subjugation of all Gaul at the Battle of Alesia in 52 BC.

  • The Samnites were, in the words of the source, "a people just as martial and as rich as the Romans," and the three Samnite Wars between 343 BC and 290 BC tested Rome more severely than any conflict since the Gallic sack. The First Samnite War, from 343 to 341 BC, was brief: Rome won battles at Mount Gaurus in 342 BC and Suessula in 341 BC, but had to withdraw to deal with a revolt by its own Latin allies.

    The Latin War forced Rome to fight on two fronts simultaneously. Victory at the Battle of Vesuvius and again at the Battle of Trifanum brought the Latin cities to heel, and they submitted largely without further resistance for the next two hundred years. Rome's relatively lenient treatment of the defeated Latins became a template for how the city managed conquered peoples.

    The Second Samnite War, running from 327 to 304 BC, was a different matter entirely. It lasted more than twenty years, involved twenty-four battles, and produced massive casualties on both sides. The Samnites seized Neapolis, and Rome recaptured it; the Samnites then inflicted a humiliating Roman defeat at the Caudine Forks, and Rome eventually reversed the tide after the Battle of Bovianum in 314 BC, steadily annexing Samnite territory until the Samnites sued for peace. Seven years later, the Samnites rose again and, in the Third Samnite War, assembled a coalition of Samnites, Gauls, Etruscans, and Umbrians at the Battle of Sentinum in 295 BC. Rome's victory there made it clear that Italian resistance to Roman dominance was no longer viable.

    The Pyrrhic War then brought Rome its first encounter with a Mediterranean military power. In 280 BC, Pyrrhus of Epirus landed a Greek army of some 25,000 men on Italian soil, along with a contingent of war elephants. The Roman army had never faced elephants before, and that inexperience cost them the Battle of Heraclea and the Battle of Ausculum. Yet Pyrrhus found Rome impossible to negotiate with, unwilling to talk as long as his army remained on Italian soil. Facing unsustainable losses and unable to find new Italian allies, Pyrrhus eventually withdrew. At the Battle of Beneventum in 275 BC, the Romans had devised counter-tactics for the elephants, including javelins, fire, and, according to one source, simply striking the animals on the head. Beneventum was indecisive, but Pyrrhus saw clearly that his army was spent. Rome moved quickly into the south, absorbed the Greek colonies of Magna Grecia, and turned its gaze toward Sicily.

  • Before 264 BC there was no Roman navy worth the name. All previous Roman wars had been fought on land. Then the First Punic War with Carthage, the great maritime power of the western Mediterranean, forced Rome to build a fleet from scratch and train sailors who had no prior experience of naval combat.

    Rome took to naval warfare, in the source's blunt phrase, "like a brick to water." The first naval engagements, such as the Battle of the Lipari Islands, were disasters. But within four years, after inventing a grappling device called the Corvus, a Roman fleet under C. Duillius beat a Carthaginian fleet at the Battle of Mylae. Further victories followed at the Battle of Tyndaris and the Battle of Cape Ecnomus, and Rome landed troops in Africa under Marcus Regulus. Regulus won the Battle of Adys and pushed Carthage toward peace talks, but the terms Rome demanded were so severe that negotiations collapsed. Carthage then hired Xanthippus, a mercenary from the Greek city-state of Sparta, to reorganise their forces. Xanthippus cut off the Roman army from its base and captured Regulus at the Battle of Tunis. Rome ultimately prevailed by winning the naval Battle of the Aegates Islands, leaving Carthage without a fleet or the money to build another.

    The Second Punic War brought a commander whose name Rome would never forget. Hannibal, of the Carthaginian Barcid family, attacked Saguntum, raised an army in Iberia, and crossed the Alps with elephants. At the first battle on Italian soil at Ticinus in 218 BC, Hannibal beat the Romans under Scipio the Elder. He then won the Battle of the Trebia, ambushed a Roman army at Lake Trasimene, and at Cannae produced what the source calls "one of the great masterpieces of tactical art." For a time, the source notes, "Hannibal seemed invincible." Yet Rome refused to negotiate. The military historian BH Liddell Hart wrote that Scipio Africanus Major revealed that "peace and war are the two wheels on which the world runs." Scipio took the war to Africa: at the Battle of Bagbrades in 203 BC his army defeated the Carthaginian forces of Hasdrubal Gisco and Syphax, Hannibal was recalled from Italy, and at the Battle of Zama, Scipio decisively defeated him. The Third Punic War was, in the source's account, "a simple punitive mission." Carthage offered surrender immediately; Rome refused and demanded the complete destruction of the city. The Carthaginians prepared to fight. After a short siege the city was stormed and its culture described as "almost totally extinguished."

  • Rome's extensive foreign campaigns created a structural problem at home. Soldiers grew loyal to their commanders rather than to the state, and the rewards of conquest, land and plunder, became the currency of political power. In the last century BC, the source counts at least twelve civil wars and rebellions.

    The Social War of 91 BC broke out when Rome's Italian allies, the Socii, who had shared the costs of Rome's campaigns without sharing the rewards, revolted. Roman troops won decisive engagements, including the Battle of Asculum, but the Socii achieved their real objective through law rather than force: the Lex Julia and Lex Plautia Papiria granted citizenship to more than 500,000 Italians.

    Lucius Cornelius Sulla then led not one but two marches on Rome, a watershed in what the source calls "the willingness of Roman troops to wage war against one another." At the Battle of the Colline Gate, at the very walls of the city, Sulla's army defeated a force composed partly of the Roman senate's own troops and their Samnite allies. The precedent he set helped pave the way for the triumvirates.

    The First Triumvirate of Caesar, Crassus, and Pompey was always uneasy. Crassus died at the Battle of Carrhae in 53 BC, which Plutarch described as Rome's greatest defeat since Hannibal. Soldiers' hands were pierced through by Parthian arrows, and Crassus himself perished. With Crassus gone, Caesar and Pompey moved toward collision. In 49 BC, Caesar crossed the Rubicon. Pompey abandoned Rome, retreated to Brundisium, and fled to Greece. Caesar defeated him decisively at Pharsalus in 48 BC despite being outnumbered two to one. Pompey was murdered in Egypt. Caesar's own assassins, the senators who called themselves the Liberators, killed him in 44 BC. The Second Triumvirate of Octavian, Antony, and Lepidus was formalised on the 26th of November, 43 BC. Its internal collapse produced one final war. At the Battle of Actium in 31 BC, Octavian destroyed Antony and Cleopatra's combined fleet near Greece using fire, and went on to take the name Augustus.

  • Augustus secured from internal threats, Rome pushed outward in every direction simultaneously. Germanic tribes in the north presented persistent challenges: in 9 AD, the Germanic leader Arminius destroyed the forces of Varus in the Battle of the Teutoburg Forest, nearly to the last man. Rome recovered and sent Germanicus, who defeated Arminius's tribes in a series of battles culminating in the Battle of the Weser River, but the Rhine eventually became the permanent limit of Roman expansion in that direction.

    In Britain, the Romans invaded in force in 43 AD, fighting their way inland through battles at the Medway, the Thames, Caer Caradoc, and Mona. After a general uprising in which the Britons sacked Colchester, St Albans, and London, Roman forces suppressed the rebellion at the Battle of Watling Street and pushed as far north as central Scotland at the Battle of Mons Graupius. Hadrian's Wall was built and manned to hold the northern frontier.

    Trajan turned east to Dacia, the territory north of the Danube. The Dacians had raided the Roman province of Moesia in 85 AD and defeated a Roman army before the Romans beat them at the Battle of Tapae in 88 AD. Trajan reopened the campaign and defeated the Dacian general Decebalus at the Second Battle of Tapae in 101 AD, but Decebalus rebuilt his forces and struck again in 105 AD. Trajan besieged and razed the Dacian capital Sarmizegethusa, then pushed further east into the Parthian Empire, bringing Rome to its greatest territorial extent.

    To the east, the Kingdom of Armenia between the Black Sea and the Caspian Sea was a recurring flashpoint between Rome and Parthia. Under Nero, Rome fought a campaign between 55 and 63 AD over Armenia. After losing control of the kingdom in 62 AD, Rome sent Gnaeus Domitius Corbulo into the territories of Vologases I of Parthia in 63 AD and returned Armenia to client status, where it remained for the next century.

  • Pyrrhus won battles against Rome and lost the war. Hannibal won battles against Rome and lost the war. Arminius destroyed three Roman legions in a forest ambush and, within a generation, Roman armies were campaigning again beyond the Rhine. The pattern is so consistent that the source identifies it as the defining characteristic of Roman military history: obstinate persistence overcoming appalling losses.

    Two types of campaign recur throughout that history. The first is the expansionist campaign, typically framed as a counter-offensive, in which each victory added territory and population. By the early empire, when expansion was halted, the source puts Rome's population at 55 million. The second type is the civil war, which plagued Rome from its foundation to its final demise.

    Rome's military served three distinct functions at once: securing its borders, exploiting conquered peoples through tribute, and maintaining internal order. That triple purpose created constant tension. Soldiers sent to secure borders came home loyal to the generals who had led them. Generals loyal to themselves, not the senate, eventually began treating Rome itself as one more city to be besieged.

    What the source calls "incompetents" who led Roman armies into catastrophic defeats were, in the long run, less damaging than the structural problem of loyalty. The Jugurthine War of 111-104 BC, a conflict in Numidia that the source describes as constituting the final Roman pacification of northern Africa, began partly because Jugurtha correctly judged that Roman commanders could be bribed. He was not entirely wrong, only strategically. Rome's final enemy was not any external force but the endemic struggle for the emperor-ship that consumed the Western Empire's resources from within, leaving it unable to resist the Huns, the Vandals, and the Germanic tribes who finally brought it down in the 5th century AD.

Common questions

What was the campaign history of the Roman military?

The campaign history of the Roman military spans from the 8th century BC, when Rome was a small city-state on the Italian Peninsula, to the fall of the Western Roman Empire in the 5th century AD. It encompasses land battles fought from Britain and Gaul in the west to Armenia and Mesopotamia in the east, including the Punic Wars, the Samnite Wars, the Pyrrhic War, wars against Macedon, the Gallic Wars, and a long sequence of civil wars.

How did Rome develop its navy during the Punic Wars?

Before the First Punic War in 264 BC, Rome had no real navy, as all prior wars had been fought on land in Italy. Forced by the conflict with Carthage to build a fleet from scratch, Rome suffered early disasters such as the Battle of the Lipari Islands. Within four years, after inventing a grappling device called the Corvus, a Roman fleet under C. Duillius defeated Carthage at the Battle of Mylae, and Rome went on to win the First Punic War through naval victory at the Battle of the Aegates Islands.

Who was Hannibal and why did he cross the Alps with elephants?

Hannibal was a member of the Barcid family of Carthaginian nobility who launched the Second Punic War by attacking Saguntum, a city with diplomatic ties to Rome. He raised an army in Iberia, crossed the Italian Alps with elephants, and invaded Italy, winning major victories at Ticinus in 218 BC, the Trebia, Lake Trasimene, and Cannae. Despite inflicting some of the worst defeats Rome ever suffered, he was ultimately recalled to Africa and defeated by Scipio Africanus Major at the Battle of Zama.

What was the Battle of the Teutoburg Forest?

The Battle of the Teutoburg Forest in 9 AD was a catastrophic Roman defeat in which the Germanic leader Arminius destroyed the forces of Varus almost to the last man. Despite the loss, Rome recovered and sent Germanicus on further campaigns against the Germanic tribes, though the Rhine eventually became the permanent limit of Roman expansion to the north.

Why did Rome fight the Social War in 91 BC?

The Social War broke out in 91 BC because Rome's Italian allies, known as the Socii, shared the military burdens of Rome's campaigns but received none of the rewards, including Roman citizenship. Although Roman troops won decisive engagements such as the Battle of Asculum, the Socii achieved their core objective through law: the Lex Julia and Lex Plautia Papiria granted citizenship to more than 500,000 Italians.

What was the Pyrrhic War and why did Pyrrhus ultimately fail against Rome?

The Pyrrhic War ran from 280 to 275 BC, when Pyrrhus of Epirus landed a Greek army of some 25,000 men and war elephants in Italy at the request of the Greek colony of Tarentum. Pyrrhus won at Heraclea and Ausculum but found Rome unwilling to negotiate while his army remained on Italian soil. Facing unsustainable losses, an inability to find new Italian allies, and a Roman alliance with Carthage, Pyrrhus withdrew. At the Battle of Beneventum in 275 BC, the Romans used javelins, fire, and direct blows to neutralise the elephants, and Pyrrhus abandoned the peninsula entirely.

All sources

1 references cited across the entry

  1. 1JournalAgricultural specialization and height in ancient and medieval EuropeNikola Koepke et al. — 1 April 2008