Major Roman deity ranking close to Jupiter and Mars. The flamines (seeflamen) 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.