Ares was the son of Zeus and Hera and was the god of war in Greek mythology. His Roman equivalent was Mars.
The most colorful tale of the Greco-Roman war god is told by Homer (Odyssey Book VIII) in his story of Ares and Aphrodite caught in a net. Ares and Aphrodite had an affair. Although Hephaestus caught his wife and Ares in a net and had many witnesses to the adultery, most of the other gods would have been happy to change places with Ares. Ares and Aphrodite had Deimos, Phobos, and Harmonia (Terror, Fear, and Harmony) as offspring .
Because Ares killed men, he was hated by the Greeks and Ares' cults were few, except in Sparta, but Ares was also known as the savior of cities and father of victory. The Roman war god, Mars, was far more popular. He was considered the father of Rome's founder, Romulus. Originally, Mars was a vegetation/fertility god.