Who is Dionysius from The Politics of Aristotle and what is their importance?

Dionysius was a Sicilian ruler in the city of Syracuse circa 350 BC. He comes up more than once in Aristotle's Politics. It is not entirely clear whether he was more of a statesman or more of a monarch. However, he is referred to in both Book 2 and again in Book 5. He is named after a god known for drunken revelry, the life force and other more instinctive and primal manifestations of human behavior and life. Whether this was because of relatively unruly and uninhibited behaviors associated with drunkenness is unclear.