Gaius Cassius Longinus was a Roman senator and general best known as a leading instigator of the plot to assassinate Julius Caesar on 15 March 44 BC. He was the brother-in-law of Brutus, another leader of the conspiracy. He commanded troops with Brutus during the Battle of Philippi against the combined forces of Mark Antony and Octavian, Caesar's former supporters, and committed suicide after being defeated by Mark Antony.

Gaius Julius Caesar Augustus, also known as Octavian, was the founder of the Roman Empire. He reigned as the first Roman emperor from 27 BC until his death in AD 14. The reign of Augustus initiated an imperial cult, as well as an era of imperial peace in which the Roman world was largely free of armed conflict. The Principate system of government was established during his reign and lasted until the Crisis of the Third Century.