The Epic of Gilgamesh, the Odyssey, Beowulf, the Greek Tragedies, Virgil's Divine Comedy, the legends of King Arthur, Don Quixote, and almost every other piece of early literature we possess are fantasies. (Don Quixote is more of a meta-parody of fantasy, but it's still in the genre.) They deal with gods and heroes, dragons and monsters, the mythic past and creation of the present.
The other genres all came from fantasy, or developed later. (Poetry, of course, is a different matter all together.)