In 77 BC Brutus, in command of the forces in Cisalpine Gaul, allied himself with Marcus Aemilius Lepidus, who as consul had tried to undo Sulla's settlements. Lepidus raised an army, which was defeated outside Rome by Quintus Lutatius Catulus. Brutus took his own forces to Mutina, where he defended the stronghold against Pompey the Great, who had been sent by the Senate to dislodge him. He withstood Pompey's attacks for a while, but was eventually forced to surrender, after which he was allowed to retire to the town of Regium Lepidi, where he was murdered by Pompey's close ally Geminius. According to Plutarch,