Mars, in Roman religion and mythology, god of war. In early Roman times he was a god of agriculture, but in later religion (when he was identified with the Greek Ares) he was primarily associated with war. Mars was the father of Romulus, the founder of the Roman nation, and, next to Jupiter, he enjoyed the highest position in Roman religion. The Salii, his priests, honored him by dancing in full armor in the Campus Martius, the site of his altar. Chariot races and the sacrifice of animals were primary features of the festivals held in his honor in March (named for him) and October. Mars was represented as an armed warrior. His attributes include the spear and shield, and the wolf and woodpecker were sacred to him. He was frequently associated with Bellona, the Roman goddess of war.