More than 7,000 years ago, the ancient Sumerians established what is considered the world's first civilization, and they credited their extraordinary achievements to their gods, the Anunnaki. See more in this scene from Season 20, Episode 7, "Secrets of the Sumerians." Watch your favorite ...

Uncover the secrets of the skulls with us in this compilation from Ancient Aliens. Watch all new episodes of Ancient Aliens, Fridays at 9/8c, and stay up to date on all of your favorite shows on The HISTORY Channel website at http://history.com/schedule. #AncientAliens Subscribe for more ...