Hades

Hades was one of the most powerful of the Olympian Gods, one of three brothers who split up the kingdom of the earth. After Hades, Zeus and Poseidon drew lots, Hades became the ruler of the Underworld. Hades didn't spend much time on Mount Olympus with the other Gods, as he preferred the quiet of his own lower Kingdom.

Remember that the Underworld of the ancient Greeks wasn't simply the Hell of modern Christian mythology. The Greeks believed that all souls went to various regions of the Underworld after death. It wasn't simply a place of punishment. So Hades had quite a large kingdom after all. Because Underworld was thought to literally exist underground, all the riches of the earth (gemstones, precious metals) were also part of Hades domain.

As mentioned in entry for Demeter, one of the myths of Hades involved his role in the kidnapping of Persephone. Though Persephone did eventually come to love Hades, he still had a few affairs during his marriage. But mostly he was a devoted husband. Though associated with death, Hades was not an evil character and was often described in myth as 'just and fair'.

Though Hades wasn't actually the God of Death (that was Thanatos), the Greeks still feared him. There were no temples dedicated to Hades and he is rarely seen in artwork from the period.

In the Roman pantheon, Hades is known as Pluto.