Eris was the Greek goddess of chaos, strife and discord. She was the daughter of Zeus and Hera; according to other myths, she was the daughter of Nyx (dark night) alone. Her opposite was Harmonia. The equivalent Roman goddesses of Eris and Harmonia were Discordia and Concordia. She had a son, Strife, whom she brought along with her when she rode her chariot to war alongside Aris.
Eris played an important role in the events that eventually led to the Trojan War. All of the Olympians had been invited to the wedding of Peleus and Thetis, who would become the parents of Achilles; however, Eris was not invited, due to her inclination to cause discord. As a means of revenge, Eris dropped the golden Apple of Discord into the party, which had the words To The Fairest One inscribed on it. Hera, Athena and Aphrodite started quarreling over who the apple should be given to, so Zeus appointed Paris, Prince of Troy, as the person to solve the dispute. The goddesses offered Paris various gifts, but he eventually picked Aphrodite, who promised him the most beautiful woman in the world; Helen, wife of Menelaus, king of Sparta.
Eris is also called Discordia.