Marcus Junius Brutus, often referred to simply as Brutus, was a Roman senator and the most famous of the assassins of Julius Caesar. After being adopted by an uncle, he used the name Quintus Servilius Caepio Brutus, but subsequently returned to his birth name. He alongside Cassius and Judas form the Three Great Traitors.
Brutus was close to General Julius Caesar, the leader of the Populares faction. However, Caesar's attempts to assume greater power for himself put him at greater odds with the Roman elite and members of the Senate. Brutus eventually came to oppose Caesar and fought on the side of the Optimates faction, led by Pompey, against Caesar's forces in the Civil War (49–45 BC). Pompey was defeated at the Battle of Pharsalus in 48 BC, after which Brutus surrendered to Caesar, who granted him amnesty.
However, the underlying political tensions that led to the war had not been resolved. Due to Caesar's increasingly monarchical behavior, several senators, calling themselves "Liberators", plotted to assassinate him. They recruited Brutus, who took a leading role in the assassination, which was carried out successfully on 15 March 44 BC. The Senate, at the request of the Consul Mark Antony, granted amnesty to the assassins. However, a popular uprising forced Brutus and his brother-in-law, fellow assassin Gaius Cassius Longinus, to leave the City of Rome.
In 43 BC Octavian, Caesar's adoptive son, became consul and immediately after taking office passed a resolution declaring Brutus and the other conspirators murderers. This led to a second civil war, in which Antony and Octavian fought the Liberatores led by Brutus and Cassius. The former decisively defeated the outnumbered armies of Brutus and Cassius at the Battle of Philippi in October 42 BC. After the battle, Brutus committed suicide. His name has since become synonymous with acts of intimate public betrayal or treason, and is perhaps only rivaled in this regard by the name of Judas. As a result, he is condemned to the worst punishment in Hell by having one of Satan's heads literally chew and gnaw on his body for all eternity in the Ninth Circle of Hell.