Battles between the Parthian Empire and the Roman Republic began in 54 BC. This first incursion against Parthia was repulsed, notably at the Battle of Carrhae (53 BC). During the Roman Liberators' civil war of the 1st Century BC, the Parthians actively supported Brutus and Cassius, invading Syria, and gaining territories in the Levant. However, the conclusion of the second Roman civil war brought a revival of Roman strength in Western Asia.