The First Triumvirate was an unofficial political alliance known as an Amitica, between three prominent Roman politicians (triumvirs) which included  Julius Caesar, Pompey the Great and Marcus Licinius Crassus. "Pompey and Caesar now formed a pact, jointly swearing to oppose all legislation of which any one of them might disapprove. It lasted from approximately 59 BCE to Crassus' defeat by the Parthians in 53 BCE. The alliance was "not at heart a union of those with the same political ideals and ambitions", but one where "all [were] seeking personal advantage."