The Gauls established themselves on a hillside about a mile to the southwest and wasted little time getting into action. With shouts of encouragement from the walls of Alesia, they launched an attack of mixed cavalry and light infantry, a tactic they had learned from the Germans. Rather than await them behind the walls, Caesar deployed his cavalry, and the ensuing battle lasted much of the day. Those in Alesia came out of their defenses and prepared to attack the inner wall when the time seemed appropriate. After a back-and-forth contest lasting all afternoon, the German cavalry finally settled the issue by massing on a flank and driving the Gallic cavalry from the field. The light infantry archers were left exposed and were run down. Meanwhile, the Gauls who had come from Alesia “returned into the town dejected and almost despairing of success.”42
The next day the relief force spent their time preparing for a direct assault on the Roman walls, making ladders and grappling hooks. They waited until midnight to begin their attack. Caesar does not mention any moonlight, but does remark that the Gallic arrows did considerable damage to his men. The return fire was equally deadly, and the attackers also found themselves badly hurt by the booby traps across the Roman front. By dawn the Gauls had made little headway against the wall, and Vercingetorix’s sally from Alesia was too late to assist.
With time quickly running out, the relief force developed a plan for a final assault. Scouts had observed a weak spot in the Roman wall of circumvallation to the northwest, where the steepness of Mt. Rea made it impossible to maintain a continuous encirclement. Sixty thousand picked men would be committed to that point, while the remainder of the relief force would attack across the plain from the southwest. Vercingetorix massed his men, according to Caesar, with “long hooks, movable penthouses, mural hooks, and other things, which he had prepared for the purpose of making a sally.”43 The flanking force left just after midnight and was in place on the far side of Mt. Rea by dawn. At noon the assault by the main force began, and this time the sally from Alesia was well coordinated.
Caesar placed himself on high ground, probably on Mt. Flavigny to the south. Pressure was intense from inside and out. The attack from Mt. Rea was the most successful: the Gauls came in waves, covered by their shields in a Roman testudo (“turtle”) defense. Part of the attackers began digging to fill in the trenches and traps while others maintained a steady arrow and sling fire to keep the defenders’ heads down. Vercingetorix and his men kept the interior forces busy by changing the focus of their attack away from the dangerous flat area to one of its edges, where the mesa fell most steeply to the contravallation. Although Caesar doesn’t specify which edge they attacked, Theodore Dodge indicates that it may have been the southern wall, as it provided the most direct aid to the attackers from the southwest; however, the wall at the north end of the Romans’ first ditch would have given the most direct aid to the attack from Mt. Rea. Whichever point they struck, it soon succeeded: “they fill the ditches with clay and hurdles, then clear the way; they tear down the rampart and breast-work with hooks.”44
Caesar sent his trusted lieutenant Labienus (according to Dodge, from the northeastern corner of the walls)45 to support the Mt. Rea defenses, with orders to attempt a sally if the defenses looked like they would break. Caesar strode through his lines, shouting encouragement to the defenders. As Vercingetorix’s men began to break through the inner wall, Caesar met them with six cohorts under Marcus Brutus, followed by seven more under Caius Fabius; they held. With the Gauls about to break through in the northwest, Labienus sent word to Caesar that he could no longer hold and would launch his sally. Clad in his red cloak, Caesar called in reserves (presumably from the northern and eastern sections) and hastened to Labienus’s aid himself. He also ordered “part of the cavalry to follow him, and part to make the circuit of the external fortifications and attack the enemy in the rear.”46 A cavalry camp existed in a flat area to the north of the walls, but Dodge argues they came from the camp atop Mt. Bussy, where Labienus had been stationed.
Once again, it was the Germans who saved the day. Struck simultaneously from both front and rear and with walls to either side, the Gauls were hemmed in and slaughtered. The repulse of Verceingetorix’s attack must have broken the spirits of those inside the contravallation for, seeing the defeat, they withdrew back into Alesia. Caesar recounted that “[a] flight of the Gauls from their camp immediately ensues on hearing of this disaster,”47 suggesting that the bulk of the forces attacking the southwest had been making little headway. The relief force soon fled their camp with fresh Roman cavalry in pursuit. Inside Alesia, Vercingetorix, succumbing to the reality of his defeat at the hands of the Romans, told his followers they could either kill him or turn him over to Caesar. They did the latter.
STARTING OFF ON DEFENSE, Caesar could implement none of the rules of the offense. Once the time came for shifting away from the defensive, however, the key characteristic of his actions at Alesia was concentration. Apparently confident in his forces facing the southwest, Caesar assumed that the key to victory was to strike the same point the enemy thought was their key. With the use of fresh reserves against a tiring enemy, Caesar struck at just the right time. With the Gauls about to penetrate the outer defenses, they must have thought that victory was in their grasp. Suddenly meeting fresh infantry to the front and cavalry from the rear, they quickly found themselves in a position from which they could neither advance nor retreat. Their surprise attack had been well planned and executed, and there was no reason for the Gauls to expect their plan to fail. When it did, however, the entire army fell apart.
Caesar then moved to exploit the sudden change in fortunes. Although his men were too tired to immediately begin a pursuit, the cavalry began within a few hours. They were easily able to catch the fleeing infantry and killed thousands more, while the remainder scattered and hurried to their respective homelands. Lacking organization, leadership, morale, or a defensible position, the Gallic army in flight was unable to do anything to hinder the pursuit. Dodge describes the siege of Alesia as “one of the most wonderful in antiquity. It equals Alexander’s siege of Tyre or Demetrius’ siege of Rhodes. The works Caesar erected were marvellous in their extent and intricacy.… [It] was a brilliant exhibition of Caesar’s ability in engineering, strategy, tactics, logistics.”48
Civil War
CAESAR ACCEPTED VERCINGETORIX’S SURRENDER and had him sent to prison in Rome, where he was executed during Caesar’s triumph some time later. The victory at Alesia broke the main resistance to Roman rule, and it required but one more season’s campaigning to quell it for good. These exhibitions of military dominance swelled Caesar’s reputation and wealth. As Michael Grant notes, “What could not be denied … was that the conquest of Gaul was a marvellous, portentous, feat of arms.”49 Caesar’s political future, however, soon faced a major challenge. Pompey was the only consul left in Rome; Crassus had gone to the East to gain some martial glory for himself, but found only disaster and a grave in fighting the Parthian army at Carrhae (53 BC). With the Triumvirate effectively dissolved, Caesar faced his own disaster if he returned to Rome: his position as governor in Gaul had kept him from prosecution for highly questionable activities he had undertaken during his political career, but his political opponents would almost certainly revive those charges if he returned to the capital. Roman law forbade him bringing his legions out of Cisalpine Gaul, yet without them, he would soon find himself in jail, or worse.
This, however, seemed the moment toward which Caesar’s entire career had pointed. Knowing a civil war would ensue when he brought his troops with him back to Italy, he announced, “The die is cast” and marched his men across the Rubicon River, the official northern boundary of Italy. Cary and Scullard write, “Caesar in 49 [BC], like Sulla in 83, was offered the choice between self-defence and political extinction. That he would put his head into a noose was hardly to be expected.”50 Despite the apparent rashness of his move, Caesar did have some initial advantages. His army had more veterans than a
ny other legions in Rome’s territories; additionally, Pompey had but two legions on hand with which to face Caesar’s eight (once they all arrived from Gaul). Caesar also had an audacious spirit that none in the Senate could match. If they had conceived of his treasonous invasion, they certainly were not ready for it to begin in January. Yet Caesar marched in midwinter and soon held key passes into central Italy. Pompey had no choice but to head south with what forces he could muster. In a race to Brundisium (Brindisi), the major port at the southeastern tip of the Italian Peninsula, Pompey arrived first, embarked with his forces, and sailed across the Adriatic with all available ships.
Albert Nofi argues that Pompey had no real alternative other than flight, but to go to Greece was not the wisest move. Hispania, he argues, would have been better:
He was technically proconsul of the Spanish provinces, had campaigned there for several years in the past, and had the favor of the populace, both Roman and native. From Spain, Pompey would be able to threaten Caesar’s recent conquests in Gaul, and possibly fall upon Italy from the Alps, for he had strong allies in the romanized southern portions of Gaul, where the city of Massilia had declared for him against Caesar. More importantly, there were six seasoned legions in Spain plus many auxiliary troops, all under commanders loyal to Pompey.… Finally, Spanish financial resources were considerable.51
Even Africa was preferable to Greece, for some of the same reasons in addition to the fact that it was centrally located, making it easier for Pompey to respond to any of Caesar’s moves. Though Greece was wealthy, it had a dearth of military resources. The troops Pompey was able to amass, while more numerous than Caesar’s, were without much experience. The populace was reasonably friendly, but they would prove fickle depending on which way the wind blew. Further, even though Pompey was able to acquire a promise from the Persians—most of his troops were moved from Persia—to remain passive, such a vow was hardly set in stone given the traditional Persian-Roman hostility.
After a brief stop in Rome to get his political affairs in order, Caesar was quickly on his way to Hispania to deal with Pompey’s forces there. Basil Liddell Hart observes, “For thus concentrating against the ‘junior partner’ he has been much criticised. But his estimate of Pompey’s inactivity was justified by the event.”52 Caesar arrived by April of 49 BC and marched to face his opponents based at Ilerda. His campaign there was swift and successful; it ended in August in victory with minimal bloodshed, and Caesar incorporated a number of Pompey’s troops into several new legions. Caesar correctly assumed that Pompey would not return to Rome, and the Spanish expedition proved brilliant in not only robbing his enemy of his resources but enriching himself militarily at the same time.53 Caesar proceeded to send troops to Sicily and Africa, as well as leaving a garrison in Hispania. With Pompey controlling the sea, Caesar needed a port and a supply of ships; Caesarian forces and ships had been besieging Massilia (Marseilles) while he was in Hispania and had forced the city’s surrender in September. Still, his “fleet” was badly outnumbered and too small to ferry his entire army from Italy to Greece.
It would seem at this point, while Caesar’s ships sailed from Gaul to Brundisium, that Pompey would have been wise to seek a naval action (particularly considering that defeating pirates had been one of the first great actions of his career), but he did not. Neither did he return to Italy, as troops were still arriving from the eastern frontier. Caesar thus marched back to Italy with the remainder of his troops and proceeded to Brundisium. Although he had twelve legions on hand, he only had sufficient shipping to embark seven understrength legions and 500 cavalry, which set sail at the beginning of the year 48 BC. They crossed unopposed, as Pompey’s admiral assumed no one would try a winter crossing. Caesar and his men arrived in Greece without incident, but found themselves badly outnumbered and short on supplies.
Pompey was a lifelong soldier, having served in his father’s command at the age of seventeen. In his younger days he had a reputation for aggressiveness and brutality, even earning the nickname “Butcher Boy.” He seems to have become “Great” as a result of showing up at the end of several conflicts and grabbing public acclaim. After a successful war in the East, he had retired from military life and spent his time in politics. Thus, when he engaged in war with Caesar he had not commanded in the field in some time, and it showed. He had had the better part of a year to expand his forces, which at this point numbered nine legions, 7,000 cavalry, and 5,000 light infantry.54 Pompey missed an opportunity to use his superior numbers, however, choosing instead to wait out the winter and engage in desultory negotiations. The remainder of Caesar’s troops arrived in April, ferried over by Mark Antony, and again Pompey’s fleet did not catch them. Liddell Hart notes that “even when Antony landed on the other side of Dyrrachium, Pompey, though centrally placed, failed to prevent Caesar and Antony effecting a junction at Tirana.”55
Caesar and Antony joined forces on the Genusus River, some thirty miles southeast of Pompey’s main base at Dyrrhachium (modern Durres, Albania). Still short of supplies, Caesar received news that Pompey’s navy had finally gone into action and captured or destroyed his entire fleet. He was now completely cut off from Italy, a vulnerability that he could not allow Pompey to exploit. Caesar sent out men to gather supplies and intercept reinforcements bound for Pompey, and then made a dash for Dyrrhachium. Although he arrived slightly ahead of Pompey’s army, he did not have sufficient time to seize the town. Pompey’s forces encamped on high ground near the harbor.
Caesar returned to his engineering ways. His men quickly began building a line of contravallation to hem Pompey’s forces against the coast (described by Liddell Hart as “original but singularly profitless”56 because the line could not cover the entire enemy line). Pompey would remain in control of the harbor, but would be unable to gather forage for his horses. Pompey’s men immediately began construction of a defensive line facing Caesar’s and both armies settled into siege warfare, extending their respective lines and engaging in frequent skirmishing. Dodge observes, “This extraordinary spectacle of Caesar bottling up Pompey, who had twice his force, by lines of circumvallation sixteen miles long, borders on the ridiculous.” Indeed, the engineering feat was too bold for even Caesar to pull off: “Caesar’s position and plan had been so eccentric that it was from the beginning doomed to failure. It was one of those cases where his enterprise outran his discretion.”57
Initially, however, Caesar’s plan to diminish Pompey’s forage was successful. Pompey therefore planned a strike against the southern flank of the lines. Learning from deserters exactly how Caesar’s works were constructed (and that at the southern end they were not yet completed), he launched an amphibious attack of three columns against the end of Caesar’s line. “In short, Caesar’s left flank was simultaneously to be attacked in front, in rear and in flank. In every way it was an admirably planned operation,” in J. F. C. Fuller’s view.58 It was also admirably executed. Caesar’s forces, attacked at dawn, were driven two miles up their lines, only to be saved by Antony’s counterattack. Pompey had been quickly fortifying a captured camp and building a new one in order to establish himself outside Caesar’s lines. Caesar launched a quick assault against this position, but was beaten back. Appian wrote, “It is probable that Pompey might then have captured [Caesar’s camp] and brought the war to an end by that one engagement had not Labienus [now on Pompey’s side], in some heaven-sent lunacy, persuaded him to pursue the fugitives instead.” He did so, to his detriment; as Caesar reportedly said, “The war would have been ended to-day in the enemy’s favour if they had had a commander who knew how to make use of victory.”59
Failing to capture Pompey’s camp, Caesar decided to forgo the siege and withdraw into the interior, looking for more supplies and hoping to locate a good spot to bring Pompey’s army into open battle. Both Caesar and Pompey were looking to be reinforced by detachments in Macedonia: Pompey’s father-in-law, Quintus Metellus Scipio, commanded two legions on the way from Syria, and C
aesar was to combine with similar numbers under Domitius Calvinus, who had been sent to delay or stop Scipio. Pompey now faced the choice of whether to leave Greece and make his way back to Rome, or stay and fight Caesar’s reinforced troops. Since Pompey had fled from Caesar once before, his pride may have prevented his departure; additionally, he knew that to bring the war to a decisive end he would have to pursue and soundly defeat Caesar’s troops. He may also have been unwilling to abandon his allies in the East, who likely would have seen their wealth confiscated and cities sacked.60
When an immediate pursuit after the battle at Dyrrhachium failed to catch Caesar, Pompey began to engage in a Fabian strategy, wearing down Caesar’s troops by keeping them on the move and unable to gather sufficient supplies. As Plutarch puts it, “For Pompey himself was cautious about hazarding a battle for so great a stake, and since he was most excellently provided with everything necessary for a long war, he thought it best to wear out and quench the vigour of the enemy, which must be short-lived.”61 Pompey thus followed, rather than pursued, Caesar. Unfortunately, he was accompanied by far too many politicians who failed to see past the immediate. They assumed that Caesar on the run was Caesar defeated, and the less they knew of warfare the more positive they were.62 They kept up an incessant demand for a quick end to the war, demands Pompey would not ignore.
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