Who is Vitellius from The Twelve Caesars and what is their importance?

Vitellius doesn't do much during his short reign, but he is hated throughout it. He is a very greedy and gluttonous man. He has his own mother starved to death because a fortune teller tells him he will live long and prosper if he outlives her. He dies a torturous death and his body is thrown in the Tiber River.