Ares, the Greek god of War, was born eons ago in the trans-dimensional plane known as Skyland, a land situated in the Sphere of the Gods. He was born to Zeus, God of Thunder, and Hera, Goddess of Marriage, both of whom were patriarch and matriarch of the Greek Pantheon, a group of Greek gods who resided on Mount Olympus in Skyland. Many of his siblings, made up the bulk of the gods of Olympus. He fell in love with Aphrodite, Goddess of Love, who bore him many children, including Phobos, God of Fear, and Deimos, God of Terror. He was also the patriarch of the Amazons. As time passed, Ares went mad with power, due to his role as the god of war. The rest of the gods of Olympus all elected to have Ares imprisoned to prevent further bloodshed. Hephaestus, God of Craftsmanship, had Ares shackled with restraints specially designed to inhibit his rage and power. As Aphrodite was the one restraining him, Ares willingly allowed himself to be imprisoned. The Gods banished him to Themyscira, where the Amazons fought to ensure that Ares could not inflict any more damage than he already had. The gods then took steps to ensure that Ares could not escape, even going as far as to wipe the memories of any gods leaving Themyscira, to prevent Phobos and Deimos from rescuing their father. Ares would eventually find a way to access the human world, and become one of Wonder Woman’s most formidable adversaries.

In the Injustice universe, Ares is nearly drained completely of power due to the lack of conflict in Superman's world. The only way to gain more power, in his eyes, is to aid the Insurgency and create more discourse.

For the voice of the god of war, you may refer to either Kevin Michael Richardson's performances as Trigon in Teen Titans OR J.H. Hertzler's performance in the Injustice video game.