Ancient Aliens: The Aliens Who Helped Ancient Cultures Survive (Season 9) | History

Archaeologists have found the remains of ancient civilizations at sites around the world that may explain how some cultures survived cataclysmic events in this clip from Season 9, Episode 3, "Aliens Among Us". #AncientAliens Subscribe for more from Ancient Aliens and other great HISTORY shows: http://histv.co/SubscribeHistoryYT Find out more about the show and watch full episodes on our site: http://po.st/AncientAliens Check out exclusive HISTORY content: History Newsletter: http://po.st/HistoryNewsletter Website - http://po.st/HistoryWeb Facebook - http://po.st/HistoryFacebook Twitter - http://po.st/HistoryTwitter "Ancient Aliens" explores the controversial theory that extraterrestrials have visited Earth for millions of years. HISTORY® is the leading destination for award-winning original series and specials that connect viewers with history in an informative, immersive, and entertaining manner across all platforms. The network’s all-original programming slate features a roster of hit series, premium documentaries, and scripted event programming.