The Ten Biggest Family Businesses in the U.S. Business Insurance lists them: Wal-Mart Wal-Mart is the world’s largest retailer and most successful family business of all time. In 1962, founder Sam Walton took his knowledge of discount retailing and opened the first Wal-Mart store in Rogers, Ark. It wasn’t long before Sam expanded his business and opened up hundreds, then thousands of stores worldwide. After Walton died in 1992, his empire was passed on to his wife and children. Rob Walton succeeded his father as chairman of Wal-Mart, and his brother, John, served on a company committee that oversaw Wal-Mart’s…