Quirinus, in Roman religion, an early god, possibly of war. Worshiped originally by the Sabines, he was one of the chief gods of ancient Rome, associated with Jupiter and Mars. In the late republic he was identified with Romulus, legendary founder of Rome.

Major Roman deity ranking close to Jupiter and Mars. The flamines (see flamen) of these three gods were the three major priests of Rome. Despite his importance, little is known about Quirinus, who was originally a god of the Sabines. He may have been another form of Mars. By the late republic he was identified with Romulus. His festival, the Quirinalia, was celebrated on February 17, and his temple was one of the oldest in Rome.

Learn more about Quirinus with a free trial on Britannica.com.