Book III

Caesar sends Servius Galba with the twelfth legion to open the Alpine pass for Roman merchants, permitting him to winter in the region if necessary.

Galba establishes winter quarters in the divided village of Octodurus, fortifying one half for his cohorts while ceding the other to the local Gauls.

The Sedani and Veragri secretly plan to attack Galba's undermanned legion, motivated by disdain for its small size, tactical advantage from the mountains, anger over hostages, and fear of Roman territorial expansion.

Galba convenes a military council to decide strategy; some propose retreat, but most recommend defending the camp as a last resort.

The Romans defend the camp rampart for six hours against overwhelming numbers, unable to rotate tired soldiers or relieve the wounded, facing superior enemy tactics of rotation.

When the Romans are exhausted and the camp is breached, centurion Baculus and tribune Volusenus convince Galba that a sudden sortie is their only hope of survival.

The Romans execute a surprise sortie from all gates, routing the enemy and slaying over a third of the 30,000-strong Gallic army, then returning to camp.

Despite winning the battle, Galba refuses to risk his luck further, burns the village, and withdraws into the provincial territories to winter safely.

Caesar believes Gaul pacified and departs for Illyricum, but a sudden war erupts when Crassus's officers are detained by the Veneti, who demand hostage exchange.

The Veneti, possessing superior naval power and controlling Atlantic ports, initiate the revolt by detaining Roman officers and convincing neighboring coastal states to join their confederacy.

Caesar orders the construction of warships on the Loire, assembles rowers, sailors, and pilots, and hastens to join the army once weather permits.

The Veneti fortify their towns, stockpile provisions, gather ships, and secure allies, believing their coastal geography, naval superiority, and unfamiliar terrain will give them advantage.

Caesar must pursue the war to punish the insult to Roman ambassadors, prevent other nations from rebellion, and divide his forces before more Gallic states confederate.

Caesar deploys Labienus to secure the Rhine and Belgae, Crassus to Aquitania to prevent Spanish aid, Sabinus to separate coastal rebels, Brutus to command the fleet, while he leads the main army.

Veneti towns built on promontories become inaccessible by land at high tide and by ships at low tide, allowing them to escape Roman assaults by sea and reoccupy other fortified positions.

Caesar describes how Veneti ships are flatter-keeled, higher-hulled, oak-built with iron-fastened benches and chain anchors, designed to withstand ocean storms better than Roman vessels.

When Roman and Gallic fleets meet, the Romans realize their ramming tactics are useless against the stronger Veneti ships and their weapons cannot reach the high-hulled vessels.

Roman soldiers improvise sharp hooks on poles to cut the rigging and sail-yards of Veneti ships, removing the enemy's primary advantage and reducing the contest to hand-to-hand combat.

With their rigging cut away, Veneti ships lose maneuverability; Roman soldiers board the enemy vessels and rout them, with most captured or destroyed until nightfall.

All Veneti forces are destroyed in the naval battle, their towns cannot be defended, they surrender unconditionally, and Caesar executes their entire senate and enslaves the population as punishment for violating ambassadorial rights.

Sabinus confronts Viridovix, who commands a large coalition including the Aulerci and Sexovii, while desperate Gallic men join the rebellion hoping for plunder and combat.

To provoke the enemy into attacking, Sabinus establishes a reputation for cowardice while secretly preparing to trap the overconfident Gauls through a planted deserter's false intelligence.

The Gauls are convinced to attack because of Sabinus's prior hesitation, the deserter's claims, their supply shortage, hope from Venetic uprising, and their natural willingness to believe favorable news.

Sabinus launches a two-gate sally against the exhausted and encumbered enemy rushing uphill, routing them decisively and allowing the cavalry to pursue and slaughter most escapees.

Crassus, arriving in Aquitania where previous Roman commanders were defeated, carefully provisions his army, secures auxiliaries, and recruits experienced men from allied cities.

The Sotiates attack Crassus's army with cavalry, and when their mounted force is routed, they deploy a hidden infantry ambush in a valley to renew the battle.

After a prolonged battle where the Sotiates rely on their valor, Crassus besieges their main town; they initially resist with sallies and mining operations but eventually surrender their arms.

Caesar describes the Aquitanian soldurii as elite devoted followers who share the life and fortune of their leader, bound by oath to die if their chief falls.

Alarmed by the fall of the Sotiates' town, neighboring Aquitanian states combine, exchange hostages, and seek Spanish auxiliaries and experienced leaders, including veterans of Sertorius's war.

Despite the enemy's superior numbers and supply advantages, Crassus's forces face deteriorating supply conditions and encirclement, compelling him to offer battle rather than be slowly starved.

The combined Aquitanian and Spanish forces, though numerous and renowned, choose instead to starve and ambush the Romans by controlling passes and provisions.

Observing the enemy's hesitation and noting how it dampens the enemy's morale while energizing his troops, Crassus ignores caution and marches to attack the enemy camp directly.

Roman soldiers fill the ditch and drive defenders from the rampart with missiles while auxiliaries provide support, but the enemy fights fiercely from their elevated position.

Roman cavalry scout the enemy camp and report that the Decuman gate side lacks equal fortification and offers an easy approach.

Crassus sends four fresh cohorts around the camp via a longer route unobserved, who breach the weak fortifications and enter the enemy camp while attention is fixed on frontal battle.

As the enemy realizes they are surrounded, they attempt to flee over the ramparts; the cavalry pursues across open plains and leaves only about 12,500 survivors out of 50,000.

Following the decisive victory, most of Aquitania surrenders and sends hostages; only the most remote nations postpone submission due to approaching winter.

With Gaul seemingly pacified, Caesar pursues the Morini and Menapii, who adopt a different strategy by retreating into forests and marshes rather than offering open battle.

Caesar systematically fells forests and piles timber as ramparts, rapidly clearing land to expose the Morini and Menapii and seize their livestock and supplies.

Severe storms and continuous rain force Caesar to suspend operations and withdraw to winter quarters among the Aulerci and Lexovii, having devastated Morini and Menapii territory.