Fall of the First Triumvirate: The First Triumvirate, an informal political alliance between Julius Caesar, Pompey the Great, and Crassus, was effectively dissolved with Caesar's death.
Renewed Civil War: Caesar's assassination sparked a new series of civil wars. His supporters, led by Mark Antony and Octavian (later known as Augustus), clashed with the assassins, led by Marcus and Decimus Brutus and Gaius Cassius Longinus.
Second Triumvirate: In 43 BC, Mark Antony, Octavian, and Marcus Lepidus formed the Second Triumvirate to defeat the assassins and avenge Caesar's death. They proscribed and executed many of Caesar's opponents.
Battle of Philippi: In 42 BC, the Second Triumvirate defeated Brutus and Cassius at the Battle of Philippi, cementing their control over the Roman Republic.
Rise of Octavian: Octavian emerged as the dominant figure after the Battle of Philippi. He and Antony divided the Roman world between themselves, with Octavian controlling the West and Antony controlling the East.
Octavian's Victory: In 31 BC, Octavian defeated Antony and his ally, Queen Cleopatra of Egypt, at the Battle of Actium. This victory consolidated Octavian's power and marked the end of the Roman Republic.
Establishment of the Roman Empire: Octavian became the sole ruler of the Roman world and adopted the title "Augustus" in 27 BC, thus establishing the Roman Empire. He implemented a series of reforms and brought peace and stability to the empire during his reign, ushering in the Augustan Age.