Battle of Alesia


The battle of Alesia or the siege of Alesia was a military confrontation fought in the year 52 B.C., in the capital of the Gallic tribe of the Mandubians, the homonymous fortress. In it the legions of the Roman Republic led by the proconsul Gaius Julius Caesar, his legates Titus Labienus and Gaius Trebonius and with Mark Antony in command of his cavalry, clashed with a confederation of Gallic tribes led by Vercingetorix, chief of the Arverni. It was a decisive battle that ensured the final victory of the Romans in the long Gallic war, the few tribes that continued to resist were defeated the following year and in 50 B.C. the conquered territory, known as Gallia Comata, would become a Roman province. The Roman Senate refused to grant Caesar the honors for his conquest, being one of the triggering factors of the civil war of the years 49 to 45 BC.

The siege of Alesia is considered one of Caesar”s great military successes and even today is used as a classic example of a siege. It has been described by numerous authors of the time, including Caesar in book VII of his Commentaries on the Gallic War.

Conquest of Gaul

The conquest of Gaul beyond the Alps began with the campaigns of the consuls Cnaeus Domitius Enobarbus in 122 B.C. and Quintus Fabius Maximus in 121 B.C.. They turned the Greek colony of Masalia into foederati of the Republic and defeated the Allobroges and Arverni. Roman sources state that in the decisive battle with the latter, on a bridge across the Rhone, the legions lost 15 troops and the Arverni 120,000, or 150,000 of their 180,000 warriors. Shortly afterwards, the Allobroges also surrendered.

The Arverno king Bituito was exhibited in the triumph of Fabius. His son, Congonetiacus, was sent as a hostage to Rome. The latter, for his victory, received the cognomen ex virtute of Alobricus. Thus was born the province of Transalpine Gaul, which served as the basis for subsequent conquests.

After finishing his consulship and thanks to what was agreed in the First Triumvirate, Gaius Julius Caesar received for five years the government of the provinces of the Transalpine and Illyria, to which was added Cisalpine Gaul on the sudden death of its governor, Quintus Caecilius Metellus Celer. To continue to rise in the politics of the Republic, Caesar needed wealth and military victories, and when in early March 58 B.C. he assumed the government of those provinces plus the command of four legions he saw his opportunity.

Caesar, under the pretext of preventing the migration of the Helvetii westward through the province of Narbonensis or the territory of their allies, the Aedui, began to intervene in the internal affairs of the tribes. After defeating the Helvetii (58 BC), he continued with the Belgic Gaul (57 BC), also faced the Germanic peoples, highlighting the defeat of Ariovisto in 58 BC. He was the first Roman to cross the Rhine, in 55 and 53 BC, and to explore Britannia, in 55 and 54 B.C.

It took Caesar several years to pacify Gaul. Partly because it extended over a very large territory that Caesar was trying to pacify with a comparatively small army.

During his campaigns Caesar combined aggressiveness, speed and risk to corner and annihilate his enemies, something he would also do in Alesia. This allowed him to compensate for his main weakness: numerical inferiority. He also proved to be an excellent motivator who knew how to encourage his men to give their best no matter the circumstances. This was in addition to the fact that he commanded a professional army born of the reforms of Gaius Marius whose units could easily surpass the Celts, who placed more value on the individual warrior, and had as their backbone the rigorous and courageous centurions. The legionaries were trained to think and act on their own initiative if the situation demanded it, as well as to blindly obey their officers. Their strength lay in the discipline of their formations.

Another aspect in which the Romans showed their superiority was in siege warfare, where Caesar used to make bypasses to isolate the hostile cities, something that weakened the morale of the defenders, who often surrendered as soon as the work began. The proconsul made no less than 17 and won in all but Gergovia. They were also extremely mobile, surprising the non-functional Celtic armies. Many tribes understood that they could not win and preferred to submit peacefully.

The problem was that all the Celtic tribes in Gaul had their own plans and it was very difficult, unless he defeated each tribe, to establish peace. Caesar was forced to fight with each of the tribes and when he had defeated them, then he could hope to secure a kind of general peace.

The last great aspect in favor of the Romans was diplomacy. They skillfully exploited tribal conflicts to recruit allies and defeat their enemies one by one. The Gauls were divided into two or three hundred tribes; the numerous smaller ones were vassals of the few larger ones. The population of these communities varied from 50,000 to 200,000 people on average.

General rebellion

In the winter of 53-52 B.C., unrest in Gaul became active again while Caesar was in Cisalpina over political and administrative issues. It all started when the Carnutes massacred all the Roman citizens at Cenabo, present-day Orleans. The Celts needed a leader who understood the Roman way of fighting and that no tribe could defeat their legions alone, someone to unite them against the common enemy, and that leader was about to appear.

The news reached a young nobleman of the powerful tribe of the Arverni, Vercingetorix, son of Celtilo, who began to gather supporters and convinced them to join the rebellion. He was expelled from Gergovia, the capital of his people, by the pro-Roman nobility, but convinced in the countryside the people most impoverished by the Roman conquest to help him and with an army he returned to the village and assumed command of his people. He proclaimed himself king of his tribe and sent messengers to his neighbors to support him, so soon the numerous revolted nations recognized his command.

Caesar left for Narbonne and there he armed the local militias and brought recruits from the Italic peninsula. He crossed the snow-covered Cevennes and marched on the territory of the Lingones, specifically Agendicus, present-day Sens, where he left the bulk of the baggage and concentrated his troops. He quickly took the oppidum (fortified villages surrounded by a murus gallicus located on hills or valleys and around which villages were established) of Vellaunoduno of the Senones, now Villon, Cénabo of the Carnutes, now Orléans, Novioduno, now Nouan-le-Fuzelier, and Avarico, now Bourges, of the Bituriges. After losing Novioduno, Vercingetorix decided to practice guerrilla warfare and scorched earth, avoiding confronting the legions head-on in pitched battles or sieges, where they were superior. Instead, taking advantage of the fact that the Romans were a relatively small army in a foreign land and that the Celts had better cavalry, he would ambush their supply parties to starve and wear them down. If forced to fight, the Gallic leader would retreat to well-defended fortresses. Vercingetorix had villages burned, wells poisoned, wagons destroyed, and all livestock and crops that could not be carried away destroyed, denying them to the Romans. However, during the campaign the rebels would be unable to do all that their leader demanded, starting with the Bithuriges, who refused to burn Avaric and decided to defend it but fell after a month of siege. The legionaries, hungry and furious, mercilessly massacred the garrison and the civilian population. It was normal at that time that, when a city or fortress resisted the enemy, if it fell to the assault, the garrison and civilians were massacred.

There he divided his army: he himself, with six legions, marched on the Arveran capital while the legate Titus Labienus, with four others, was sent against the Senones and Parsees. Caesar failed before the walls of Gergovia, a town that Vercingetorix was not willing to lose because it was the capital of his people. The proconsul had to retreat to Agendicus to meet with Labienus, who had just crushed the Celts in Lutetia. During the siege of Gergovia, a contingent of 10,000 Aedui (main allies of the Romans) sent to help Caesar was tricked by their commanders into joining the rebellion, claiming that the Romans had killed their compatriots enlisted as auxiliaries. The proconsul reacted immediately and went out to convince the Aedui of the falsity of that accusation. The Celts resolved to join the proconsular army. This did not prevent the rest of the tribe from joining the rebellion, killing the entire garrison of Novioduno and freeing all of Caesar”s Gallic hostages. That was their administrative capital and so the rebels seized their treasury, grain stock, replacement horses and the best part of their baggage.

In view of this new success, a council was held in Bibracte, capital of the Aedui, attended by representatives of all the Gallic tribes. Vercingetorix was recognized as generalissimo of his armies and all the tribes joined him, only Lingones, Oars and Treveros refused to participate. He immediately demanded his allies to deliver hostages and send horsemen until he had 15,000, keeping the infantry he already had. He then recruited 10,000 infantry and 800 Aedui horsemen. He sent ambassadors with the Allobroges to raise Narbonese Gaul.

While continuing to threaten Roman supply lines, the warlord retreated to Alesia. Caesar pursued him with 3000 infantry and numerous Germanic horsemen. Vercingetorix prepared an ambush, but the eager Celts attacked early and the Germanics defeated them around the Vingeanne River, with 3000 Gallic horsemen perishing. The next day Caesar reached Alesia from the east, south of Mount Bussy.


The proconsular army was led by him and his legates Titus Labienus, Mark Antony and Gaius Trebonius and consisted of ten Roman legions. Labienus, his second in command in the war and the only legate with praetor”s powers, stood out. Caesar had appointed him at the beginning of his campaigns because he had greater military experience, being able to command independent armies with great skill. When the proconsul was outside Gaul he acted as legatus pro praetore.

The legionaries were volunteers recruited from the Italian peninsula, although Caesar allowed inhabitants of Cisalpine Gaul, usually considered less Roman, to enter and be promoted in his army, gaining their loyalty. These heavy infantry units were his core but he also had numerous auxiliary troops serving according to their specialty: Numidian light cavalry, Germanic and Thracian heavy cavalry, Balearic and Ligurian slingers, Cretan archers and light infantry. The Roman army had to be followed by a real “second army following in its wake to trade”: sellers of horses or cloth, blacksmiths, jewelers, fortune tellers, musicians, actors, jugglers, procurers, prostitutes, prostitutes and other fortune seekers.

During the Second Punic War each legion was composed of about 3000 heavy infantry, 1200 light infantry and 300 horsemen. With the Marian reforms these distinctions were eliminated and armament standardized, and although the number of Roman heavy cavalry remained the same, the heavy infantry grew to 4000 to 5000, or even 6000 soldiers. The lightly armed Roman infantrymen (vélites) were replaced with an increasing contingent of foreign auxiliaries. During the later civil war, the veteran Caesarian legions would hopefully pass 3000 legionaries. It was also not uncommon for the armies of the late Republic to include war elephants and artillery such as ballistas, onagros and scorpiones, each operated by a dozen men, although they were usually used in camp defense, river crossings or sieges.

These legions included infantry, cavalry and artillery as well as civilian administrative personnel, military musicians, engineers and medical specialists. There was also a servile contingent known as calones, who were in charge of the maintenance and transportation of the legionaries” material, ranging from cooks to stable boys. Finally, there were the suppliers and drivers of pack animals called muliones.

According to the American historian Paul Davis in 1999 Caesar had 40 000 legionaries, 5000 Germanic mercenaries on horseback and 10 000 auxiliaries of all kinds. He later raised the number of auxiliaries to 15 000 and kept the others. The American military historian Kimberly Kagan believes that would be about 48,000 legionaries and auxiliaries in total but the fighting and hunger suffered before during the campaign would have depleted their forces; their infantry would be half of the Gallic troops. Peter A. Inker says that each legion was composed of 4000 soldiers and 800 horsemen on average, considering that Caesar must have had 10 according to the author, the results are 40 000 legionaries and 8000 horsemen. The British Nic Fields believes that they totaled less than 50,000 troops in total. Hans Delbrück believes that among all would be 70 000, The Australian Stephen Dando-Collins gives the highest figure for the Caesarian army: 80 000.

According to the American military historian Theodore Ayrault Dodge, Caesar must have had about 50 000 legionaries, 5000 horsemen and perhaps about 10 000 auxiliary infantrymen, mainly Gallic. According to him, to besiege more than 80 000 Celts it was impossible for them to be less than half or the risk of breaking the siege would have been too high to take that risk. At the beginning of the campaign, the numbers were probably the same, except for the Gallic light infantry, which were probably twice as many and halved after the desertion of the Aedui. Only one fifth of the cavalry were Germanic.


The Gallic allied army of Vercingetorix included, according to Caesar, 80,000 infantry warriors after Gergovia. Caesar mentions that after the escape of the cavalry there were still 80,000 warriors inside the fortress. Florus says that the garrison of Alesia totaled 250,000 men (40,000 at Avaric and 80,000 at Gergovia).

Dodge interprets the 80,000 as the total army and the infantry as 65,000. Richard Gabriel believes that the Gallic cavalry numbered 10,000 to 15,000 mounted cavalry. At Alesia they camped on the east side of the village after digging a ditch and erecting a wall six feet (just over two meters) high for protection. This was because, although some troops were encamped inside the city, most were outside. Archaeological studies reveal that the plateau did not have enough space for such a large army plus auxiliary personnel and civilians. Another point against such a figure is provided by Delbrück; if true, Vercingetorix could well have left a strong reserve in Alesia and sent some 60 000 warriors to a massive attack when the Romans were building the trenches, preventing them from working. According to him, the garrison would not exceed 20 000 warriors and his reinforcements 50 000.

The French archaeologist François Lenormant believes in Caesar”s figures. Based on detailed studies of the ruins of Alesia and calculating the space needed to house each warrior on foot or mounted plus their supplies, he calculated that the oppidum could not have more than twenty thousand inhabitants and would be unable to accommodate more than thirty thousand infantrymen. Using the same method with the space located on the eastern slope of Mount Auxois, where the rest of the Gallic army was located, Lenormant believed that Vercingetorix could have 50,000 infantry and 10,000 cavalry.

The rescue army, again according to Caesar, numbered 240 000 infantrymen and 8000 horsemen, although Strabo speaks of 400 000 These figures are not necessarily false, but must be taken with care. Caesar, for political and propagandistic reasons, tended to exaggerate the number of enemy soldiers and casualties. Apparently, Vercingetorix had demanded from each tribe a contribution in a certain number of warriors.

The figures would be as follows: eduos and vassals (segusiavos, ambivaretos, aulercos branovices and blanovios) were to contribute 35 000 warriors, arvernos and vassals (eleutetos, cadurcos, gábalos and velavios) another so much, sécuanos, senones, bituriges, sántonos, rutenos and carnutes 12 000 each, and arémoricos (coriosolites, redones, ambibarios, cáletes, osismos, vénetos and unelos) 10 000 each, the Bellovaks offered the same, but in the end they only contributed 2,000 rauracians and boyos contributed an equally reduced contingent each, pictones, thuronians, parisians and helvetians 8,000 each, suesiones eleuterios, ambianos, mediomátricos, petrocorios, nervios, morinos, nitióbroges and aulercos cenómanos 5,000 each, atrebates 4,000, and veliocases, lexovios and aulercos eburovices 3,000 each. Never before had so many tribes allied against Caesar at once; of the 85 major tribes, about 40 contributed to the effort, taking about a month to assemble the relief force.

Kagan believes that the Gauls were actually a quarter of Caesar”s number, so the besieged would be 20,000 and the reinforcements 60,000, barely twice as many in infantry as the enemy. Thus, the besieged would be 20 000 and the reinforcements 60 000, barely twice as many in infantry as the enemy. Most modern historians agree that the followers of Vercingetorix must have been fewer than the proconsul states, and that the reinforcements must have been 80 000 to 100 000 warriors. Today, the latter figure is the most advocated.

Alesia was situated on Mount Auxois, which ended in a plateau surrounded by steep slopes and bordered by the rivers Lutosa (present-day Ose) to the north, Oserain to the south and Brenne to the west. The first two were tributaries of the upper Sequana (Seine). This plateau measured a mile and a quarter from east to west and half a mile from north to south, with a height of 500 feet above the surrounding valleys. At its western end was a plain and to the east the Gallic army was encamped. To the east (the Pennevelle stands out), north (the Bussy to the northeast and the Rea to the northwest stand out) and south (the Flavicny stands out) there was a line of mountains of equal height to the Auxois, separated by small and deep valleys through which the aforementioned rivers passed.

The choice to take refuge in Alesia was a fatal mistake for the Arverian leader, his refuge had turned out to be a trap. Unlike Gergovia, here Caesar was able to block all supplies to the city thanks to his massive siege works and not even the salvation army could help Vercingetorix, who had to surrender, ensuring Roman rule in Gaul. The siege began in early September of the Julian calendar according to the Italian historian Albino Garzetti.

Siege works

To ensure a complete blockade of Alesia, Caesar had a series of fortifications built. He first seized the hills to the north, south and east of the village, then began preparing the ground where the defenses would be, began building 23 fortified redoubts (castella) on the hillsides, then the main cavalry and infantry camps, and finally linked them with an inner ring of trenches called a countervalation 11 Roman miles (about 15 kilometers) long. A water-filled dike 20 feet (about 6 meters) deep and straight-walled was also built across the Laumes plain between the Ose and Oserain rivers west of Alesia, which was 400 feet (600 meters) in front of the line of Roman fortifications.

Caesar established his infantry camps preferably in the surrounding hills while those of his cavalry near the watercourses. The two of the infantry camps were on the hill south of Alesia, where the attack was more predictable, supported by a triple line of trenches; the other two were in the hills to the northeast and northwest. Three of the cavalry camps were on the great western plain and a fourth to the north, with a shallower trench than those of the infantry. Estimates based on archaeological studies say that the northwestern camp could hold up to two legions, the southern ones one legion each and the northeastern one up to three. The other legions were distributed among the various minor forts.

Each fortification had a line of palisades (vallum) twelve feet (3.5 meters) high made of fences (lorica) and preceded by two trenches fifteen feet (4.5 meters) deep, the one furthest from the fortifications was filled with water from the nearby rivers. He added to the palisade battlements (pinna), and an embankment (agger) with sharpened stakes (cervi) at its base to prevent it from being scaled and provided for a three-story (25 meters high) watchtower with artillery every 80 feet (almost 24 meters).

Finally, Caesar decided to add to the defenses, to precede them, eight rows of thick trunks with their main branches sharpened, and partially sunk in trenches to prevent their removal. The legionaries called them cippi. To reach them, one had to cross a field of eight rows of lilia, “lilies,” tied to the earth to prevent their removal and placed in wells filled with hardened clay. And even before that, there were small holes filled with steel spikes called stimuli, “stimuli,” and hidden by grass and leaves. These works were finished in just three weeks.

Cavalry clashes

There were constant sorties by the Celtic cavalry with the intention of stopping the works, reaching its climax after the completion of the dam, when the Celtic horsemen defeated their Roman counterparts on the plain of Laumes. However, the legions that were building in the sector reacted and formed up for battle, waiting for the enemy infantry to come out, this encouraged the Germanic horsemen to charge the Gauls and after a fierce combat they prevailed. The Gauls were trapped between the Germanics and the ditch, which was where they were being pushed towards, many having to abandon their mounts in order to save themselves. It was the moment when the proconsul ordered his legions to advance, making the Celts flee towards Alesia, but Vercingetorix had closed the gates and they were trapped and massacred. The Germans retreated after killing many enemies and capturing numerous horses.

Vercingetorix understood that the same would not happen from Gergovia, he could not stop the siege works and would soon be surrounded, “It was not wise to give a second chance to a general of Caesar”s ability.” That night he ordered all his cavalry to escape along the beds of the two rivers, taking advantage of the fact that the siege works were not finished. He asked them to return to their tribes and call to arms as many able-bodied men as they could to liberate the fortress. In the words of British historian John Sadler: “What was needed was a relief army, one as massive, as overwhelming as a monster that would break through Caesar”s lines and end the war once and for all.” so he personally guarded it and ordered a series of measures demanding their obedience on pain of death: cattle and grain were distributed very rationally among the men. He also ordered his forces to barricade themselves inside the fortress.

Learning of this danger from his spies, Caesar ordered the construction of a new defensive system called the circumvallation, an outer ring of fortifications 14 Roman miles (20 kilometers) long. To avoid dangerous collecting sorties, the proconsul had a 30-day supply of grain and fodder stockpiled and put on rationing.

Death of Alesia civilians

The siege had been going on for about six weeks and the conditions inside the fortress were getting worse and worse and finally they ran out of grain. The Celtic chiefs convened a council to decide what to do, listening to different options, highlighting that of the Arverno nobleman Critognato, who was totally against capitulating and proposed to devour those who could not fight (non-combatants and wounded). For during the invasion of Cimbrians and Teutons allowed them to resist in their forts and recover their lands when the enemy retreated. If not, the Roman conquest would be certain.

The Gallic leaders decided to expel all those who could not fight in order to avoid having to follow Critognatus” advice. The Mandubians, inhabitants of the fortress, had to expel their families. The mass of non-combatants arrived at the Roman positions where they begged to be taken as slaves and fed. They were probably the poorest (and least influential) people in the village. Caesar ordered that they not be admitted as he had no grain to feed thousands of extra mouths and told them to return to the city, but when they did their leaders would not let them in. They starved to death in the no man”s land between Alesia and the counter-valley. Modern archaeological studies indicate that the population of the fortified village may well have been 5000 to 10 000. Some speak of as many as 12 000 starving to death among civilians and the wounded.

Gallic reinforcements arrive

The Gauls held a council of their nobility and decided that, to avoid concentrating an army so large that they could neither command nor feed it, instead of doing as Vercingetorix ordered and taking all the fit men, each tribe would make a contribution required by the council. Their commanders were the atrebate Comius, the Aedui Viridomarus and Eporedorix, and the Arvernus Vercasivelaunus, cousin of Vercingetorix. Each tribal contingent was to be commanded by chiefs of their own tribe. certain that the Romans could not handle such a vast host with either a front or rear attack. Probably because of the obvious problems of mobilizing, organizing and feeding a large number of men with different commanders, each tribe sent the required contingent to a rallying point as close as possible to Alesia.

According to Garzetti, the Gallic liberation army could not have appeared before the beginning of October according to the Julian calendar. It immediately occupied the hill of Mussy-la-Fosse, less than a mile from the Roman fortifications.

First breakup attempt

The next day, the Gallic reinforcements placed all their cavalry on the plain to the west of the Roman lines while their infantry remained on the high ground.They distributed archers and light infantry among their horsemen to support them.They also began to fortify their camp.Upon realizing this, the besieged men left the city euphoric, for from the heights they could see their comrades perfectly and both forces gave each other encouragement.However, the defenders did not attempt to organize an attack on the Roman positions.

Caesar responded by ordering his men to take up their positions in the fortifications and send out his cavalry. The Celtic archers killed or wounded many Romans, allowing the proconsul”s horsemen to be cornered against the ring road, which produced euphoria among the Gauls in Alesia. From noon to dusk, both cavalries fought fiercely with no clear victor until the Germanic horsemen charged and put the Celts to flight.They soon caught up with the Gallic archers and slaughtered them.The Roman horsemen pursued the vanquished back to their camp.This demoralized the defenders of Alesia.

Second breakup attempt

The Gauls spent all the next day making iron hooks and ladders until, silently at midnight, they approached the Roman defenses on the plain. After a thunderous shout to frighten the surprised defenders, they began to tear down obstacles and attack the legionaries with slings, rocks and arrows. Many are hit in the chaos of the night. Many were hit in the chaos of the night, armed with sashes to cover the ditches, ladders, flagpoles and iron hooks to scale the palisade and musculi (heavy wicker parapets) to protect themselves from Roman projectiles. The legionaries responded using their scorpions. Vercingetorix also heard the commotion and ordered his troops to charge at the sound of trumpets from Alesia. The Romans responded from the defenses with projectiles, then the legates of the sector, Trebonius and Antonius, ordered the troops in the most recondite forts to go quickly to the points where the sounds of combat were heard.

Finally, when dawn seemed to be approaching the Celts retreated in fear that the Roman cavalry would come out from another sector and attack them in the rear. The defenders of Alesia lost time filling in the trenches, suffering heavy losses during the attack against the Roman defenses in the southern hills. When they realized that their comrades were retreating they decided to abandon the attack.

Last breakup attempt

After two unsuccessful attempts to break the siege, the Gauls asked what to do and after talking to locals, they found the right spot to attack. Their leaders knew that the warriors were becoming demoralized and needed a victory. They found that on Mount Rhea, north of Alesia, there was a camp that was not properly included in the system of defenses due to the slope. There were stationed the legates Gaius Antistio Reginus (I legion) and Gaius Caninius Rebilus (XI legion).

After sending scouts to reconnoiter the terrain, the 60,000 bravest warriors were selected. The arvernus Vercasivelauno, cousin of the besieged warlord, was chosen to command them. He decided to leave before dawn and position himself behind the mountain to hide, allowing his men to rest until the time came to attack. Then the Gauls charged against the aforementioned camp, while the cavalry attacked along the western plain and other units attacked different sectors as a distraction. Vercingetorix saw the events from the heights, he was anxious to break the siege for the needs of his men, and went out with hooks, ladders and everything he could need to overcome the defenses, ordering to attack the areas that seemed weaker. They uttered thunderous shouts trying to frighten their enemies.The Romans could barely defend each affected area because of their numerical inferiority.Their various positions communicated through light signals using polished metal objects, being able to quickly know where and how many enemies were attacking each sector.In contrast, when a line of Celtic assailants was exhausted, a replacement contingent immediately arrived.Both sides knew that the moment was decisive, the last chance to break the siege for the Gauls and a life and death struggle for the Romans.

The proconsul understood this and sent reinforcements to the most threatened area, which was where Vercasivelauno was attacking, a location where the slope of the terrain made the Romans very vulnerable. The Gauls were already inside the fortifications fighting and had dislodged the Romans from many watchtowers with their arrows. They had also filled in the trenches with earth and boards, cleared their path of traps, pulled out the stakes and pulled down part of the palisade. Some legionaries threw projectiles and others repulsed the attackers by forming shields with their shields. Every now and then, the Celts were relieved by new contingents, while the Romans were at the limit of their strength.

This was the absolute crisis; the battle, the campaign, the entire six years of war were at stake. Vercasivelauno was about to break through, an irresistible avalanche of warriors about to tear a gaping hole in the defenses. The besieged and their reinforcements would be united. Gaul would have won and Rome would have lost.

Caesar, understanding the danger in that sector, had previously sent his second, Labienus, with 6 cohorts, then the young Decimus Junius Brutus Albinus with as many others and the legate Gaius Fabius with 7 more. Probably from the southern positions, the least threatened at that time.

Caesar decided to march himself into the fray, reminding his men that everything achieved in the previous years of war depended on that battle. He took 4 cohorts and some cavalry from a nearby redoubt. crimson paludamentum (Roman commanders usually wore purple and admirals navy blue). Finally, the Germanic mercenary cavalry made a sortie and began to approach the Celts from the left to charge on Vercasivelauno”s rear. Soon after, while the Gallic attackers were fighting hand-to-hand with the legionaries they see approaching from behind a body of cavalry, which encourages the Roman cohorts to charge on them. Many Celts are killed and many others captured.

Seeing these events, the defenders of Alesia retreat to the safety of their fortress. When news of the disaster reaches the camp of the liberating army, the Celts begin to retreat in panic but the Romans were too exhausted to pursue them. Only after midnight is a corps of 3000 infantry and all the cavalry sent to overtake the Gallic rearguard and disperse them.

Surrender of Vercingetorix

The day after the defeat a council of Gallic chiefs was convened in Alesia. It must have been mid-October of the Julian calendar. Vercingetorix arranged for the assembly to advise him on what to do: commit suicide or surrender himself alive. Shortly afterwards, ambassadors were sent to negotiate with the enemy. Caesar demanded that they all surrender alive, chiefs and warriors. According to mythology, the defeated leader decided to offer his life in an act of devotio to save those of his followers. The Celts then began to leave to be disarmed and taken captive.

Caesar, in De bello Gallico, describes that he set up his proconsular curule seat in front of the fortifications of his camp and there received the Gallic ringleaders, including Vercingetorix. According to Dion Cassius, Vercingetorix approached Caesar, who was seated, without any herald”s announcement and pushing some who were close to him, causing alarm as he was very tall and with his armor looked imposing. This caused alarm as he was very tall and in his armor looked imposing. When order was restored, without speaking, he knelt before the proconsul with his hands folded in supplication. Caesar showed little mercy and had him put in chains. Florus says that the Arvernus king came out with his horse and armor to surrender to Caesar, exclaiming in Latin before him, “Here I am, a strong man you defeated, a very strong man.” Plutarch maintains that the leader of all Gaul beautifully harnessed his horse and went out through the gates of Alesia, circled around the dais where Caesar was and finally dismounted, removed his armor, weapons (spear, sword and helmet) and ornaments (phalera and torque), knelt down and remained silent before the proconsul until he was taken under guard. The scene looks like a ritual oblation very common among Celts and Germanic.

The French nationalist historiography of the 19th century, led by Henri Martin, based on Plutarch”s account and whose maximum example is Royer”s painting, represents the moment as a ritual sacrifice where the young Gallic warlord enters the Roman camp on a white horse and rides through the lined-up legionaries, surrendering his weapons with disdain as a last challenge before a victorious, rancorous and implacable Caesar.

Australian historical novelist Colleen McCullough, in her 1997 work Caesar, imagines the Roman general wearing civilian proconsular robes trimmed in purple, not his armor, as he was accepting the surrender of the fortress. He would wear an ivory cylinder to represent his imperium and a civilian crown for valor shown in combat. His chair would be on a dais shared only with Aulus Hirtius, his private secretary, who was in toga, while his officers would be around him dressed in their best armor and with their helmets in their arms. On the right would be those of higher rank (Labienus with a scarlet sash representing his imperium, Trebonius, Fabius, Sextus, Cicero, Sulpicius, Antistius and Rebilus) and on the left the lesser ones (Brutus, Antonius, Basilus, Plancus, Tullus and Rutilius). All the legionaries would be watching Vercingetorix approach flanked by rows of horsemen, with jewels adorning his arms, neck, belt, shawl, winged helmet and the band across his chest. Trusted companions would help him dismount and strip off the garments, kneel and bow his head in submission. Then would begin the shouts of jubilation of the Romans until Hirtius would order a servant to deliver a small table, ink, a pen and a scroll with the formal surrender of Alesia for the Arverno king to sign. He would then be removed in chains from the site.

The French historian Christian Goudineau denies such a scenario. Drawing a parallel between Alesia and the surrender of the village of Aduatuca (57 BC), he believes it more likely that after the diplomatic exchange mentioned by Caesar, the Celtic leader surrendered unarmed and his men threw their weapons from the walls of the oppidum. His compatriot, archaeologist Jean-Louis Brunaux, argues that Vercingetorix was not brought alone before Caesar but chained and surrounded by centurions.

Subsequent events

The proconsul Julius Caesar gave all the possessions of the defeated as booty to his men and to each legionary he gave a Celt as a slave to sell, that is to say, about 40 000 Gauls enslaved at least. The officers received several. All the soldiers became rich with what they obtained and the legates could feel like kings. After the victory he marched to the lands of the Aedui to guarantee their loyalty, he also sent ambassadors with the Arverni to subdue and deliver hostages. Caesar had separated the warriors of these powerful tribes and after guaranteeing their loyalty he ordered the 20,000 Aedui and Arverni to be freed. The casualties of the liberating army are unknown, but from what Caesar indicated, they suffered enormous losses, both in dead and prisoners. After learning of the victory in Italy, the Roman Senate ordered 20 days of celebrations. However, his political enemies, such as Marcus Porcius Cato, proposed to hand him over in chains as a war criminal to the Celts.

Then he sent his legions to the winter quarters: Labienus went with two legions and cavalry with the Sécuans, later to be joined by Marcus Sempronius Rutilius;Lucius Minucius Basilus was sent with the oars with two legions in order to keep the Bélovaks from attacking them; Gaius Antistius Reginus and Gaius Fabius were sent with the Ambivaretes; Titus Sextius with the Bituriges and Gaius Caninius Rebilus with the Ruthenians with one legion each; Quintus Tullius Cicero and Publius Sulpicius garrisoned the Aedui territories to guarantee the supply of grain.

The great Gallic rebellion that had united almost all its tribes under the same cause and organization was over, there would never again be a massive revolt, only isolated cases of resistance. The Romans spent the year 51 B.C. fighting the last pockets of resistance, the Bituriges, the Carnutes and especially the Belgic tribes. The last major battle took place at Uxelodunus in southwestern Gaul. By the time winter came all the tribes seemed subdued and Roman garrisons were distributed throughout the country. During 50 B.C. there was no fighting and this peace was maintained during the coming Roman civil wars. All attempts at uprisings were harshly crushed and the region was not considered completely pacified until the reign of Augustus. Occasional uprisings continued to occur from time to time until the middle of the first century, but Gaul would remain Roman until the conquest of the Franks five centuries later. Many Gauls preferred to flee to Germania or Britannia rather than live under the Roman yoke.

Vercingetorix was sent to a cell in the Mamertine prison, where he waited six years to be exhibited in Caesar”s triumphal parade, after which he was strangled in prison. The proconsul was known for his clemency, but by committing his final victory in Gaul at such a critical moment for his political position in Rome (after the death of Marcus Licinius Crassus at Carras), the Roman general wished to be ruthless.


The victory was due, to a great extent, to the fact that in the final assault most of the Celts did not participate, in fact, many remained in the western plain without intervening. In spite of this dispersion of the enemy forces, the multiple and massive attack must have overwhelmed the proconsular army. Alesia demonstrated the proconsul”s skills as a military commander and the discipline and courage of his legions in an extreme situation, as well as his ability to recognize what to do at each instant, for example, sending the Germanic cavalry at the right moment. Another important factor was the division of command in the relief army, organized in several tribal councils.

During this campaign the proconsul demonstrated his military prowess, reacting quickly and unexpectedly to rebel movements, concentrating his army and taking his fortresses one by one. He recovered from a heavy defeat at Gergovia and built an impressive double system of fortifications for the final battle, defeating an enemy more than five times more numerous. Vercingetorix”s plan was good, to deny the decisive battle and attack the Romans at their weak point: the supplies. When he broke away from this he condemned himself to defeat.

The victory proved decisive for the end of the war. Strangely, Caesar”s greatest victories, Alesia and Pharsalus, always came after defeats, Gergovia and Dirrachium respectively.

The Gallic War was a campaign of aggressive expansion made by an ambitious warlord eager to advance his political career, something perfectly valid in Roman values, where wealth was needed for bribes and patronage and the prestige of military victories for promotion. That is the reason, for example, that in his writings Caesar was concerned to always highlight his victories and to hold others responsible for his defeats. Three times he experienced a disaster: in the first expedition to Britain, where his fleet was almost sunk by a storm; in Gergovia, where his legions attacked without waiting for his order; and in Aduatuca, when his lieutenants were defeated and killed.

His campaigns of conquest are usually divided into two main stages: the first constituted by the initial conquests and the second by the quelling of the Celtic revolts, subdividing the latter into the punitive campaigns against Germanic and Britons, the rebellion of Ambiorix and finally that of Vercingetorix.

In the first century B.C. ambitious Romans eager for glory, power and wealth led wars of conquest to places hardly known before by their compatriots. This war, it is estimated, cost the lives of 400 000 Gauls according to Veleius Paterculus, 1 192 000 according to Pliny the Elder (although including enemies killed in civil wars) The latter also states that another million Celts were enslaved and a total of eight hundred villas and three hundred tribes were subdued. Apianus says that Caesar faced four million barbarians in this war, enslaving a quarter and killing in battle an even greater number, subduing four hundred tribes and twice as many villages. Fields estimates that about two million Gauls, mostly men, were killed in the seven years of war. Some historians have classified these campaigns as genocide, although this is a matter of strong debate. Excessive violence was very common in the wars of Antiquity and the Romans were no exception, as they were famous for being warlike. However, it should be mentioned that it was very rare for them to massacre an entire enemy community, usually preferring to execute their leaders and enslave the population, which was much more lucrative for the troops. The Romans only committed large massacres when the enemy community really threatened their power or committed some atonement. This was considered to exact bloodthirsty revenge and was very often to punish a tribe considered allied or submissive that rebelled against them.

Caesar was surprised on several occasions by the Gallic revolts, although I don”t think he was very surprised because revolts were quite frequent. Many of the conquests that Caesar achieved in Gaul had not been very difficult and many of the tribes had surrendered to Caesar as soon as he had entered their territories, so the tribes had not really been defeated in battles. Perhaps it was inevitable that they would rebel against Caesar when they began to realize that their independence was being stolen from them.

Since the reforms of Marius, half a century earlier, the Republic ceased to have a national army and private militias loyal to rich men who could pay, organize and command them began to appear, marginalizing the republican authorities to the mere role of legitimizing their authority; with armies loyal to their person, these warlords could subvert the traditional order to seize supreme power. They were made up of volunteers from the capite censi (proletarians), that is, people without property who roamed the cities, and who became professional soldiers loyal to the general who paid them and not to the Republic. Previously, the legions were made up of small and medium rural landowners who did their military service to exercise their political rights and paid for their own equipment. As the Republic expanded, campaigns became longer, preventing them from working their lands, and large numbers of slaves began to arrive to work the estates of the wealthy. This led to the bankruptcy of many of these minor landowners, reducing the number of recruits for the legions and increasing the number of vagrants in a period when the Republic needed more and better soldiers. Marius” solution was obvious. This new type of soldier fought because the best means of enriching himself in his time for men of his class was through plunder and the slaves they could obtain. This brought about the “most intense period of conquest in the history of Rome”.

The right to serve in the army ceased to be a privilege, the only path to civic honors. (…) Little by little the honorable service of the Roman citizen to the fatherland was prostituted to the lowly rank of soldier of fortune.

Thus the human reserves increased just when Rome needed soldiers, as after the disaster of Arausio, and the small landowners, who had been trying for years to evade the levies, were freed from the levies. Moreover, after the Social War, citizenship had been given to all Italic socii, eliminating also the distinction between Roman legions and Italic alae, allowing to increase the armies from four legions recruited per year to ten according to the need.

Economically speaking, the conquest of Gaul meant an annual tribute for the Republic of forty million sesterces and hundreds of thousands of kilometers of fertile land rich in natural resources. It also opened to Roman trade a market of millions of people. Caesar would use the wealth acquired from the sale of thousands of slaves to buy political support, order the construction of public buildings in Gaul, Hispania, Italy, Greece and Asia, ordered the construction of a new Forum for one hundred million sesterces, held great gladiatorial spectacles, public feasts well supplied with wine and saw to it that each of his veterans received a piece of arable land for their retirement.

With their conquests, both Caesar and Pompey possessed fortunes much greater than that of Crassus at the time of his death, estimated at two hundred million sesterces. During the last century of the Republic, certain noble senators and those of consular rank managed to amass fortunes thanks to their numerous and large estates, several of them exceeding one hundred million sesterces in properties. Among them were Marius, Lucius Cornelius Sulla or Lucius Licinius Lucullus. Just to explain the magnitude of the fortunes, for the second century it was estimated that the annual budget of the entire imperial army was four to five hundred million sesterces. Apart from them, there was a large number of lower ranking senators who did not reach the highest magistracies but possessed modest fortunes.

Popular culture

In the Asterix comics (The Green Shield), this uncertainty about the location of Alesia is humorously characterized by a reference to Gaulish pride. The album shows Asterix and Obelix talking to other Gauls familiar with the campaign, who quickly recall the victory of Vercingetorix in Gergovia, but refuse to talk about Alesia, and insist that no one knows where it is.

For many years, the exact location of the battle site remained forgotten. The main candidates for Alesia were two: Alaise in Franche-Comté and Alise-Sainte-Reine in Côte-d”Or, where Emperor Napoleon III of France, following archaeological excavations carried out between 1861 and 1865 by Colonel Eugéne-Georges Stoffel, built a statue dedicated to Vercingetorix. More recent theories suggest Chaux-des-Crotenay, in Jura, but Alise-Sainte-Reine remains the most probable theory, which would be confirmed by recent archaeological excavations and aerial research carried out by Michel Reddé between 1991 and 1995.



  1. Batalla de Alesia
  2. Battle of Alesia