Editing Second Triumvirate (section)

=== Liberators' civil war, 42&nbsp;BC ===
{{further|Liberators' civil war|Battle of Philippi}}
[[File:Brutuscng752619.jpg|thumb|Coin, minted by [[Marcus Junius Brutus]] in 42&nbsp;BC, depicting himself on left and commemorating the [[assassination of Julius Caesar]] on the [[Ides of March]] on right.]]
[[File:Roman-Empire-43BC.png|thumb|Division of territory at the foundation of the Triumvirate (43&nbsp;BC).{{col-begin}}{{col-2}}{{legend|#7D87FF|Sextus Pompey}}{{legend|#ED1C24|Brutus & Cassius}}{{legend|#FED250|Rome's client kingdoms}}{{legend|#FF8C8C|Ptolemaic Egypt}}{{col-end}}]]

Preparations for war on the tyrannicides started promptly. In Rome, the new year saw [[Julius Caesar]] consecrated as a [[Divus|god]].{{sfn|Pelling|1996|p=5}} With the triumvirs having slaughtered their political enemies in Italy, they moved with some forty legions against Brutus and Cassius in the east: Lepidus remained in Italy – supervised by two pro-Antony governors – while Antony and Octavian moved to cross the [[Adriatic Sea|Adriatic]] for [[Macedonia (Roman province)|Macedonia]].{{sfn|Pelling|1996|p=5}}

While some eight legions had crossed the Adriatic early in the year, the naval forces of the ''liberatores'' and of Sextus Pompey were able to interdict the triumvir's transports. Octavian dispatched [[Quintus Salvius Salvidienus Rufus]] against Sextus Pompey's base of operations in Sicily, resulting in a bloody but indecisive battle near [[Messina|Messana]].{{sfn|Pelling|1996|pp=5–6}} It took until summer for the triumvirs to move all their armies into Macedonia.{{sfn|Pelling|1996|p=6}} Through early 42&nbsp;BC, Brutus and Cassius were active in Asia sacking cities and forcing tribute from the provincials to pay their own soldiers.{{sfn|Tempest|2017|pp=245–46}} The ''liberatores'', busy, delayed marching west (perhaps an error in retrospect); they moved to intercept Antony and Octavian only in mid-July.<ref>{{harvnb|Pelling|1996|pp=6–7|ps=. "It would surely have been better to move west quickly... and seek to isolate the advanced force on the west coast of Greece [and] play the 48 campaign over again ... the Liberators' brutal treatment [of Asia] did nothing for their posthumous moral reputation. Perhaps it also cost them the war".}}</ref>

The triumvirs' advance forces reached Philippi first, but were outmanoeuvred and forced to retreat. Brutus and Cassius, hugely outnumbering the advance force, reached Philippi in early September, forcing the triumvirs' advance forces to retreat. Antony and Octavian arrived some days later. The ''liberatores'' first attempted to avoid battle in light of the triumvirs' weak supply situation. But Antony was successful in forcing battle with the construction of earthworks on Cassius' flank.{{sfn|Pelling|1996|pp=7–8}}

The ''liberatores'' accepted battle, triggering the first battle: Brutus fought Octavian, Cassius fought Antony. Brutus' forces were successful and stormed Octavian's camp and destroying three of Octavian's legions. Cassius' forces, however, were less successful; Antony was able to storm Cassius' camp around the same time. Believing the battle was lost, Cassius committed suicide.{{sfn|Pelling|1996|p=8}} In the aftermath, Cassius' forces were amalgamated into Brutus' army.{{sfn|Tempest|2017|pp=203–4}}

Three weeks later, on 23 October 42&nbsp;BC, Brutus offered battle again, fearing desertions and possible cutting of his supply lines.{{sfn|Pelling|1996|p=8}} In this second battle, the combined forces of Antony and Octavian defeated Brutus' army. Antony was largely the victor – Octavian apparently spent most of the first battle hiding in a marsh{{sfnm|Pelling|1996|1p=8|Tempest|2017|2p=202}} – and had forced the ''liberatores'' to battle and defeat twice.{{sfn|Pelling|1996|p=8}} In the aftermath, Brutus committed suicide.{{Sfn|Tempest|2017|p=208}}