Post-Caesarian civil war

Battle of Mutina
Date April 21, 43 BC Location Northern Italy Result Tactical Republican victory, Strategic Mark Antony victory (Antony prevents encirclement of his forces, the enemy consul was killed), Octavian and the Republic sign a treaty with Antony
Belligerents
Roman Republic	Mark Antony's forces
Commanders and leaders
Octavian Aulus Hirtius † Gaius Vibius Pansa Caetronianus †	Mark Antony
Strength
45,000	20,000
Casualties and losses
8,000	6,000

The Battle of Mutina was fought on April 21, 43 BC between the forces of Mark Antony and the forces of Octavian, Gaius Vibius Pansa Caetronianus and Aulus Hirtius, who were providing aid to Decimus Junius Brutus Albinus besieged by Mark Antony.

The battle took place a week after the bloody and uncertain Battle of Forum Gallorum ended with heavy losses on both sides and the mortal wounding of consul Vibius Pansa. The other consul Aulus Hirtius and the young Caesar Octavian launched a direct attack on the camps of Mark Antony in order to break the front of encirclement around Mutina (modern day Modena). The fighting was very fierce and bloody; the Republican troops raided camps but Antony's veterans counterattacked; Hirtius the consul was killed in the melee; Octavius Caesar personally intervened and managed to avoid defeat, while Decimus Brutus also participated in the fighting with part of his forces locked in the city.

After the battle, Mark Antony decided to give up the siege and retreated with skill west along the Via Emilia, escaping the enemy forces and reconnecting with reinforcements of lieutenant Publius Ventidius Basso. The battle of April 21, 43 BC ended the brief war of Modena in favor of the Republicans allied with Octavian but soon the situation would change with the formation of the Second Triumvirate of Antony, Octavian and Lepidus.

Around one year after Julius Caesar's murder, negotiations between the Roman Senate and Antony broke off. Antony was unhappy with the province he was due to govern, Macedonia, after his year as Consul of Rome. Macedonia was too far away if trouble were to threaten him in the capital, Rome. So he exchanged the post for a five-year term in Cisalpine Gaul. From that vantage point he could overawe the capital, and if need be intervene directly, as Caesar did in 44 BC. It did not matter that a governor had been selected who was already in possession of the province. This was Decimus Junius Brutus Albinus, a distant relative of Marcus Junius Brutus and a onetime follower of Julius Caesar. He had lost confidence in the Dictator and taken part in his assassination on the Ides of March. Antony planned to transfer his legions in Macedonia to Italy, lead them northward and unseat Decimus Brutus.

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