The First and Second Triumvirates of Rome

Silver denarius of Julius Caesar at time of First Triumvirate. De Agostini / G. Dagli Orti / Getty Images

A triumvirate is a system of government wherein three people share the highest political power. The term originated in Rome during the final collapse of the republic; it literally means the rule of three men (tres viri). The members of a triumvirate may or may not be elected and may or may not rule in accordance with existing legal norms.

The First Triumvirate

An alliance of Julius CaesarPompey (Pompeius Magnus) and Marcus Licinius Crassus ruled Rome from 60 BCE to 54 BCE.

These three men consolidated power in the waning days of Republican Rome. Although Rome had expanded far beyond central Italy, its political institutions -- established when Rome was just one more small city-state among others -- failed to keep pace. Technically, Rome was still just a city on the Tiber River, governed by a Senate; provincial governors largely ruled outside of Italy and with few exceptions, the people of the provinces lacked the same dignity and rights that Romans (i.e., people who lived in Rome) enjoyed.

For a century before the First Triumvirate, the republic was rocked by slave revolts, pressure from Gallic tribes to the north, corruption in the provinces and civil wars. Powerful men -- more powerful than the Senate, at times -- occasionally exercised informal authority with the walls of Rome.

Against that backdrop, Caesar, Pompey, and Crassus aligned to bring order out of chaos but the order lasted a scant six years. The three men ruled until 54 BCE. In 53, Crassus was killed and by 48, Caesar defeated Pompey at Pharsalus and ruled alone until his assassination in the Senate in 44.

The Second Triumvirate

The Second Triumvirate consisted of Octavian (Augustus), Marcus Aemilius Lepidus and Mark Antony. The Second Triumvirate was an official body created in 43 B.C., known as Triumviri Rei Publicae Constituendae Consulari Potestate. Consular power was assigned to the three men. Usually, there were only two elected consuls. The triumvirate, despite a five-year term limit, was renewed for a second term.

The Second Triumvirate differed from the first insofar as it was a legal entity explicitly endorsed by the Senate, not a private agreement among strongmen. However, the Second suffered the same fate as the First: Internal bickering and jealousy led to its weakening and collapse.

First to fall was Lepidus. After a power play against Octavian, he was stripped of all of his offices except for Pontifex Maximus in 36 and later banished to a remote island. Antony -- having lived since 40 with Cleopatra of Egypt and growing increasingly isolated from the power politics of Rome -- was decisively defeated in 31 at the Battle of Actium and thereafter committed suicide with Cleopatra in 30.

By 27, Octavian had retitled himself Augustus, effectively becoming the first emperor of Rome. Although Augustus paid particular care to use the language of the republic, thus maintaining a fiction of republicanism well into the first and second centuries CE, the power of the Senate and its consuls had been broken and the Roman Empire began its nearly half-millennium of influence across the Meditteranean world.