Battle of Ilerda

Infobox Military Conflict
conflict=Battle of Ilerda

caption=
partof=Caesar's civil war
date=June-August 49 BC
place=Ilerda (modern-day Lleida), Spain
result=Populares victory
combatant1=Populares
combatant2=Optimates
commander1=Julius Caesar
commander2=Lucius Afranius Marcus Petreius Marcus Terentius Varro
strength1=
strength2=|7 legionscasualties1=
casualties2=|7 legions surrendered

The Battle of Ilerda took place in June 49 BC between the forces of Julius Caesar and the Spanish army of Pompey the Great, lead by his legates Lucius Afranius and Marcus Petreius. Unlike many other of the battles of the civil war, this was more a campaign of maneuvre than actual fighting.

Introduction

After having driven the optimates from Italy, in March 49 BC, Caesar turned his attention to the Republican army in the Spanish provinces. On his way to Spain, Caesar was delayed when in April the port city of Massilia rebelled under Lucius Domitius Ahenobarbus. Leaving the siege of Massilia to be conducted by Gaius Trebonius and Decimus Junius Brutus Albinus, Caesar moved on to Hispania Citerior to reinforce the three legions he had sent there as an advance guard under his legate Fabius.

The Ilerda Campaign

When he arrived on the Spanish border, Caesar was able to seize the Pyrenees passes from the republicans and march into Spain. Near Ilerda, the Pompeians made camp on a hill and Caesar camped on another near by lower hill with the only thing separating the two armies the river Sicoris. Caesar caused his troops to dig a huge trench in order to force on the one path to the huge hill between them and the city of Ilerda. By light both armies raced towards the hill and the Pompeians occupied it first as they had the shorter distance to travel. As they occupied the most strategic position of the area, this put Caesar's army under pressure, to relieve this pressure Caesar dispatched the cavalry to fall on the Pompeians at the other side. Both sides pulled back and a stalemate appeared.

The spring storms and the melting snow from the mountains then caused flooding, which particularly affected the lower situated Caesarians whose camp was flooded. This meant that the Caesarian troops were unable to forage and famine struck the army, accompanied by disease. When the flood of the river Sicoris finally withdrew, the Caesarians built a bridge over it and caused Petreius and Afranius to abandon their camp and the city of Ilerda and a retreat towards a second republican army under Marcus Terentius Varro was started.

Caesar ordered a pursuit which overtook the retreating rear guard of the republican army and he was able to block the route on which the republicans were retreating. The two armies again camped close to each other and confraternization between the two armies started. Petreius, wanting to stop this confraternization, had the Caesarian soldiers who had wandered into the republican camp rounded up and killed. After this the republicans again retreated towards Ilerda, only to become besieged by the Caesarians in their new camp. By July 30, Caesar had completely surrounded Afranius and Petreius's army. On August 2, the Pompeian 5 legions strong army in Ilerda surrendered to Caesar.

Aftermath

After the surrender of the republican main army in Spain, Caesar then marched towards Varro in Hispania Ulterior, who at once without a fight submitted to him and surrendered another two legions. After this Caesar left his legate Quintus Cassius Longinus - the brother of Gaius Cassius Longinus - in command of Spain with four of the legions, partly made up of men who had surrendered and gone over to the Caesarian camp, and returned with the rest of his army to Massilia and its siege.

References

* Caesar's "Commentarii de Bello Civili".