Lucius Tarquinius Collatinus

Lucius Tarquinius Ar. f. Ar. n. Collatinus was one of the first consuls of the Roman Republic in 509 BC, together with Lucius Junius Brutus. The two men were leaders of the revolution which overthrew the Roman monarchy; ironically Collatinus was forced to resign his office and go into exile as a result of the hatred he had helped engender in the people against the former ruling house.

Collatinus was the son of Arruns Tarquinius, better known as Egerius, a nephew of Lucius Tarquinius Priscus, the fifth King of Rome. Through an accident, Arruns had been born into poverty, but when his uncle subdued the Latin town of Collatia, he was placed in command of the Roman garrison there. The surname Collatinus was derived from this town.

Collatinus married Lucretia, daughter of Spurius Lucretius Tricipitinus. According to legend, while Collatinus was away from home, his cousin, Sextus Tarquinius, son of the king, Lucius Tarquinius Superbus, came to his house by night. Forcing himself upon Lucretia, Sextus threatened to kill her, together with a slave, and tell her husband that he had caught her in the act of adultery with the slave, unless she should accede to his desire. After his departure, Lucretia sent for her husband and father, and recounted the events to them. Despite their entreaties and protests of her innocence, Lucretia then plunged a dagger into her breast in expiation of her shame.

Enraged by his cousin's deed, Collatinus and his father-in-law brought news of the crime before the people. They were supported by Brutus, the king's nephew, and others who had suffered various cruelties at the hands of the king and his sons. While the king was away on a campaign, the conspirators barred the gates of Rome and established a republican government, headed by two consuls, so that one man should not be master of Rome. Brutus and Collatinus were the first consuls, and set about the defense of the city.

...
Wikipedia