Roman name: Mars
Function: god of war
Ares was the son of Zeus and Hera, but because of his bloodthirstiness, not many of the gods cared much for him, except Aphrodite. Ares and Aphrodite had a long-standing affair [see Aphrodite]. Ares had four children with her as well as many children with Thracian women [map]. He was the father of several of the Argonauts and of the Amazon Queen, Penthesileia.
Ares was worshipped mostly in areas outside of Greece and thus had barbaric connotations (in Greek, the word “barbaros” [βάρβαρος] means “foreign”). Thrace and Scythia were centers for his worship, and in myth he was largely associated with the Amazons and Colchians [map]. The belt Heracles stole from the Amazon Queen Hippolyte had been given to her by Ares [see 12 Labors of Heracles]. The grove in which the Golden Fleece rested was sacred to Ares.
Despite his bloodthirstiness, Ares was often beaten by others. Athena wounded him gravely while fighting at Troy. Heracles managed to take him down four times while fighting at Pylus. The giants Otus and Ephialtes trapped him in a pot and he was stuck there for over a year until Hermes rescued him.
The Greeks were not fond of Ares because he was so bloodthirsty. In fact, Zeus tells Ares, “To me, you are the most hateful of the gods who hold Olympus, because quarreling is always dear to you, and war and battles” (Iliad 5.890-91). Zeus’ outburst is particularly striking because Ares was his own son. On the other hand, Mars was always a favorite god of the Romans. Mars was the protector of Rome, and he was their patron god similar to the way Athena was for the Athenians. Mars was also especially important to the Romans because he was not only their war god but also an agricultural god.