 The Triumvirate would have to conquer the rest of Rome's holdings; Brutus and Cassius held the Eastern Mediterranean, and Sextus Pompey held the Mediterranean islands.On 27 November 43 BC, the Triumvirate was formally established by a new law, the lex Titia.Octavian and Antony reinforced their alliance through Octavian's marriage to Antony's stepdaughter, Clodia Pulchra.