Who is the king of the Underworld?

Hades

Who is the legendary Greek hero of Homer's Iliad known for his incredible strength and fierce temper? Who almost killed his son Jonathan inadvertently due to a rash vow about not eating before victory? In what country did the tradition of putting up a Christmas tree begin? Name the composer who became deaf later in life but continued to compose music? Who became Brazil’s first Emperor in 1822?