On October 23, 42 BC, Marcus Junius Brutus, Roman senator and the most famous of the assassins of Julius Caesar, committed suicide at about 42 (b. 85 BC). From the article:
"Brutus dies by suicide
Marcus Junius Brutus, a leading conspirator in the assassination of Julius Caesar, dies by suicide after his defeat at the second battle of Philippi.
Two years before, Brutus had joined Gaius Cassius Longinus in the plot against the Roman dictator Julius Caesar, believing he was striking a blow for the restoration of the Roman Republic. However, the result of Caesar’s assassination was to plunge the Roman world into a new round of civil wars, with the Republican forces of Brutus and Cassius vying for supremacy against Octavian and Mark Antony. After being defeated by Antony at a battle in Philippi, Greece, in October 42 B.C., Cassius killed himself. On October 23, Brutus’ army was crushed by Octavian and Antony at a second encounter at Philippi, and Brutus took his own life.
Antony and Octavian soon turned against each other, and in 27 B.C. the Roman Republic was lost forever with the ascendance of Octavian as Augustus Caesar, the first emperor of Rome."