Marcus Porcius Cato (; 234–149 BC), also known as Cato the Censor (Latin: Censorius), the Elder and the Wise, was a Roman soldier, senator, and historian known for his conservatism and opposition to Hellenization. He was the first to write history in Latin with his Origines, a now fragmentary work on the history of Rome. His work De agri cultura, a rambling work on agriculture, farming, rituals, and recipes, is the oldest extant prose written in the Latin language. His epithet "Elder" distinguishes him from his great-grandson Cato the Younger, who opposed Julius Caesar.

He came from an ancient Plebeian family who were noted for their military service. Like his forefathers, Cato was devoted to agriculture when not serving in the army. Having attracted the attention of Lucius Valerius Flaccus, he was brought to Rome and began to follow the cursus honorum: he was successively military tribune (214 BC), quaestor (204), aedile (199), praetor (198), consul (195) together with Flaccus, and censor (184). As praetor, he expelled usurers from Sardinia. As censor, he tried to save Rome's ancestral customs and combat Hellenistic influences.