Well due to Caesar's increasingly monarchial behaviour, there happened to be several senators (his enemies) that took up the name of the Liberators. They plotted to assassinate Caesar. So they recruited Brutus (who was close to General Julius Caesar, the leader of the Populares faction). He took on a major role in the assassination of caesar. It was carried out successfully on March 15, 44 B.C. The Senate, at the request of the Consul Mark Antony, granted amnesty(or immunity) to the assassins. But... a populist uprising forced Brutus and his brother-in-law, (fellow assassin) Gaius to flee the City of Rome for their lives. On the other hand in 43 B.C., Caesar's grandnephew, Consul Gaius Octavian Caesar, after taking office immediately passed a resolution declaring the conspirators or the assassination, (including Brutus, plus the others, murderers). Finally leading up to the Liberators' civil war, pitting the erstwhile supporters of Caesar, under the Second Triumvirate, wishing both to gain power for themselves and avenge his death, against those who opposed him. Octavian combined his troops with those of Antony, and together they decisively defeated the outnumbered armies of Brutus and Cassius at the Battle of Philippi in October 42 B.C. After the battle, Brutus committed suicide.
