The Second Triumvirate is the name historians give to the official political alliance of Octavian (later known as Augustus), Marcus Aemilius Lepidus, and Mark Antony, formed on 26 November 43 BC with the enactment of the Lex Titia, the adoption of which marked the end of the Roman Republic. The Triumvirate existed for two five-year terms, covering the period 43 BC – 33 BC.
Unlike the earlier First Triumvirate, the Second Triumvirate was an official, legally established institution, whose overwhelming power in the Roman state was given full legal sanction and whose imperium maius outranked that of all other magistrates, including the consuls.
Octavian, despite his youth, extorted from the Senate the post of suffect consul (consul suffectus) for 43 BC. He had been warring with Antony and Lepidus in upper Italia. In October 43 they agreed to unite and seize power; they met near Bononia (now Bologna ).
The Triumvirate was legally established in 43 BC as the Triumviri Rei Publicae Constituendae Consulari Potestate ("Triumvirs for Confirming the Republic with Consular Power", invariably abbreviated as "III VIR RPC"). It possessed supreme political authority. The only other office which had ever been qualified "for confirming the Republic" was the dictatorship of Lucius Cornelius Sulla. The only limit on the powers of the Triumvirate was the five-year term set by law.
A historical oddity of the Triumvirate is that it was, in effect, a three-man directorate with dictatorial powers which included Antony, who as consul in 44 BC had obtained a lex Antonia which had abolished the dictatorship and expunged it from the Republic's constitutions. As had been the case with both Sulla and Julius Caesar during their dictatorships, the members of the Triumvirate saw no contradiction between holding a supraconsular office and the consulate itself simultaneously (Lepidus was consul in 42 BC, Antony in 34 BC, and Octavian in 33 BC).
In order to refill the treasury, the Triumvirs decided to resort to proscription.[4] As all three had been partisans of Caesar, their choices of targets were somewhat peculiar. The most notable victim,Marcus Tullius Cicero, who had opposed Caesar and excoriated Antony in his Philippics, came as no surprise; nor did the proscription of Marcus Favonius, a follower of Cato and a constant opponent of both triumvirates; but the proscription of Caesar's legate Quintus Tullius Cicero (Marcus Tullius Cicero's younger brother) seems to be motivated by pure spite. Perhaps the most shocking proscription was that of Caesar's legate Lucius Iulius Caesar, Caesar's first cousin once removed (and Antony's uncle) and one of Caesar's closest friends.
Octavian's colleague in the consulate that year, his cousin (and nephew of Caesar), Quintus Pedius, died before the proscriptions got underway. Octavian himself resigned shortly after, allowing the appointment of a second pair of suffect consuls (the original consuls for the year, Caesar's legate Aulus Hirtius and Gaius Vibius Pansa Caetronianus, had died fighting on the Senate's side of the first civil war to follow Caesar's death, that between the Senate and Mark Antony himself). This became a broad pattern of the Triumvirate's two terms; during the ten years of the Triumvirate (43 BC – 33 BC), there were 42 consuls in office, rather than the expected 20.
The Caesarean background of the Triumvirs made it no surprise that immediately after the conclusion of the first civil war of the post-Caesar period, they immediately set about prosecuting a second: Caesar's murderers Marcus Junius Brutus and Gaius Cassius Longinus had usurped control of most of the Eastern provinces, including Macedonia, Asia Minor, and Syria. In 42 BC, Octavian and Antony set out to war, defeating Brutus and Cassius in two battles fought at Philippi.
After the Battle, the Triumvirs agreed to divide the provinces of the Republic into spheres of influence. Octavian — who had begun calling himself "Divi filius" ("son of the divinity") after Caesar's deification as Divus Iulius ("the Divine Julius") and now styled himself simply "Imperator Caesar" — took control of the West, Antony of the East, and Lepidus of Hispania and Africa. This pact was enacted by theTreaty of Brundisium (Brundisium Agreement) in September 40 BC.
While Antony cemented his hold in the East and reformed the provincial administration (like Sulla's provincial reforms, Caesar's had been quietly ignored after his death), Octavian tightened his grip on the West and nominally oversaw a campaign against the pirate commanderSextus Pompeius (the campaign was actually commanded by Octavian's lieutenant, Marcus Vipsanius Agrippa), which culminated in victory in 36 BC. Agrippa had been consul in 37 BC and had secured the Triumvirate's renewal for a second five-year term.
Like the First Triumvirate, the Second Triumvirate was ultimately unstable and could not withstand internal jealousies and ambitions. Antony detested Octavian and spent most of his time in the East, while Lepidus favoured Antony but felt himself obscured by both his colleagues, despite having succeeded Caesar as Pontifex Maximus in 43 BC. Consequently, Lepidus cooperated in Octavian's campaign against Pompeius (son of Gnaeus Pompeius Magnus) but foolishly attempted to seize control of Octavian's victorious legions. Octavian unilaterally expelled Lepidus from the Triumvirate, but allowed him to retain his Pontificate.
Despite having married Octavia, Octavian's sister, in 40 BC (Octavian had married Antony's stepdaughter Clodia Pulchra three years earlier), Antony openly lived in Alexandria with Cleopatra VII of Egypt, even siring children with her. A master of propaganda, Octavian turned public opinion against his colleague. When the Triumvirate's second term expired in 33 BC, Antony continued to use the title Triumvir; Octavian, opting to distance himself from Antony, refrained from using it.
Octavian illegally obtained Antony's will in July 32 BC and exposed it to the Roman public: it promised substantial legacies to Antony's children by Cleopatra, and left instructions for shipping his body to Alexandria for burial. Rome was outraged, and the Senate declared war against Cleopatra, an important distinction, because Octavian did not want the Roman people to consider it a civil war.
Octavian's forces decisively defeated those of Antony and Cleopatra at the Battle of Actium in Greece in September 31 BC, chasing them toEgypt in 30 BC. Both Antony and Cleopatra committed suicide in Alexandria, and Octavian personally took control of Egypt and Alexandria (Egyptian chronologies treat Octavian as Cleopatra's successor as Pharaoh).
Octavian's ally Gaius Maecenas forestalled a conspiracy allegedly organised by Lepidus's son (31 BC). With the complete defeat of Antony and the marginalisation of Lepidus, Octavian, having restyled himself "Augustus" in 27 BC, remained as the sole master of the Roman world, and proceeded to establish the Principate as the first Roman "emperor".