Along with Lepidus and Octavian (later Augustus), he formed the Second Triumvirate. To seal the alliance Antony married Octavian's sister, Octavia (see Julio-Claudian Family Tree). After the triumvirate came to an end, he was decisively defeated by Octavian in the naval battle of Actium.
He committed suicide prior to Octavian's entry into Alexandria in 30 BC.