Part P.T. Barnum, part Billy Graham, his vision transformed shopping in America and made him one of the world's richest men. Sam Walton started life out as a poor depression era baby in Oklahoma's dust bowl. He became the richest man in the nation, single-handedly building his chain of Wal-Mart stores into the world's largest retailer. See how Sam built his empire from a single store to a global chain in less than thirty years, sneaking up on established names like Sears and K-Mart and passing them by before they could adjust to his challenge.