After Octavian, Antony, and Rebida formed the "Three-Headed Alliance" in 43 BC, in order to destroy the hostile forces in the city of Rome, a great purge of the Senate began, and those who were included in the list of public enemies were executed without trial and their entire property confiscated, and about 300 senators and 2,000 knights were killed, including Cicero, who had supported Octavian