Marcus Porcius Cato Uticensis (95-46 BC), known as Cato the Younger, was a Roman political figure whose opposition to Pompey and Caesar helped hasten the collapse of the Roman Republic.

Orphaned when a child and raised in the house of his uncle M. Livius Drusus, the reformer, Cato early cultivated habits of austerity and made a great show of political and moral probity. After serving as military tribune in Macedonia (67-66 B.C.), he toured Asia to prepare himself for public life. As quaestor, or minister of finance, Cato was notable for his punishment of corrupt treasury clerks and the strict rectitude of his accounts. But he was not free of favoritism. As tribune elect in 63, he prosecuted for electoral bribery one of the men who defeated Catiline for the consulship, exempting the other because he was a relative.

Cato's fiery speech on December 5 led the Senate to...