To provide for quick action in times of emergency, Roman Senators could appoint someone to exercise supreme control over Rome for a specified period (usually six months). Because this leader's word was law, he was called a dictator (a Latin word meaning "I have spoken").

In 458 BC, the Roman general Cincinnatus was called away from his farm to meet the threat of an advancing army. He dutifully marched off to war, defeated the enemy, returned to Rome, and obediently resigned. Cincinnatus had been dictator for sixteen days.

[According to traditional accounts, Cincinnatus was briefly called upon again in 439 BC.]