Roman historian, born at Amiternum, in the territory of the Sabines, and attained the quæstorship and the tribunate, though a plebeian; for a misdemeanour was expelled the Senate; joined Cæsar's party in the Civil War, and became governor of Numidia; enriched himself by extortions, and returned to Rome a rich man, and gave himself to literature; wrote the "Catiline Conspiracy," and the "War with Jugurtha," among other works, in a terse and forcible style, and was the precursor of Livy and Tacitus; as a writer he affects the moralist, though he lived in vice (86-35 B.C.).