Ares

Ares is the son of Zeus and monarch of the Olympian Gods. Ares was worshiped as the god of war in both ancient Greece and ancient Rome. After the rise of Christianity in the Roman Empire, Zeus allowed the worship of the Olympians to die out, and Ares was no longer allowed to act as patron god of warriors. As a result over the ensuing centuries Ares grew increasingly dissatisfied with Zeus' rule. He has tried to conquer Olympus on several occasions sometimes in league with his uncle Pluto, god of the Olympian underworld.

(Source: Marvel Database)