Most classical historians agree the "Epic of Gilgamesh" exerted substantial influence on both the "Iliad" and the "Odyssey", two epic poems written in ancient Greek during the 8th century BC. The story of Gilgamesh's birth is described in an anecdote from "On the Nature of Animals" by the Greek writer Aelian (2nd century AD). Aelian relates that Gilgamesh's grandfather kept his mother under guard to prevent her from becoming pregnant, because an oracle had told him that his grandson would overthrow him. She became pregnant and the guards threw the child off a tower, but an eagle rescued him mid-fall and delivered him safely to an orchard, where the gardener raised him.