Agrippa, Marcus Vipsanius (c. 63–12 BC)

Roman general and admiral. He was instrumental in the successful campaigns and rise to power of the emperor Augustus. He commanded the victorious fleet at the Battle of Actium and married Augustus' daughter Julia.

Agrippa used his great wealth to the advantage of the Roman people and Augustus's regime; he built the Pantheon, a new bridge over the Tiber, and the first public baths. He also rebuilt the sewers, and greatly improved the water supply of Rome with aqueducts and a new distribution network.

Following the murder of Julius Caesar, Agrippa went to Rome with Octavian (later Augustus), who had been a fellow student at Apollonia, and helped him to raise an army from Caesar's veterans and supporters. Although he did not play a prominent part in the campaign against Brutus and Cassius, he was the architect of Octavian's decisive victories at sea, first over Sextus Pompeius in 36 BC, then over Mark Antony in 31 BC. His political advancement was irregular but rapid; he was praetor in 40 BC, consul in 37 BC, aedile in 33 BC, and consul again 28–27 BC (thereby violating the rule specifying that there be ten years between consulships).

In 29 BC he helped Octavian carry out a reform of the Senate, expelling some members and co-opting new ones. Agrippa remained loyal to the Augustus throughout his life; when Augustus became ill in 23 BC, it was to Agrippa that he gave his signet ring, presumably intending thereby to make him his successor. On his recovery Augustus sent Agrippa to govern the eastern half of the empire, and offered his daughter Julia's hand in marriage, making it clear that Agrippa's sons, Gaius and Lucius Caesar, would be his heirs. Agrippa became virtually joint ruler with Augustus in 18 BC, when he was given the power of a tribune in addition to his proconsular command.