April 14 - Battle of Forum Gallorum : Mark Antony, besieging Caesar's assassin Decimus Brutus in Mutina, defeats the forces of the consul Pansa , but is then immediately defeated by the army of the other consul, Hirtius.
April 21 - Antony is again defeated in the Battle of Mutina by a coalition of Octavian, Decimus Brutus, and the two consuls of the year. Antony withdraws into Transalpine Gaul (France).
July-August – Antony is again at the head of a large army, and Octavian enters Rome in force without opposition. It is clear that Cicero’s plan to divide them against each other has failed.
November - Octavian meets Antony and Lepidus in Bononia, and the three enter into an official five-year autocratic pact, the Second Triumvirate.