Who Really Discovered America? explores the possibility a number of explorers discovered the New World long before Christopher Columbus staked his claim in 1492. No less than a dozen cultures have tales of these adventurers woven into their histories, but they are noticeably absent in American history books. This documentary explores the possibility the Chinese, Japanese, Polynesians, Norse, Welsh, Irish, Ancient Hebrews and the Solutreans all made it to the Americas earlier than Columbus. We rebuild the ships, trace the routes, test the artifacts and analyze blood evidence to finally learn the answer to one of the greatest mysteries of all time - who really discovered America.