William John Potts was born on July 25, 1917 in East York (now part of Toronto), Ontario to John Potts and Alice Mary Wilken. After encouragement from a brother to attend a wrestling session at a local gym, he began being training to be a wrestler by Phillip Lawson. Initially using the name Bill Potts, he made his wrestling debut in 1936 and by June he was participating in a tour of the United Kingdom and Ireland with other Ontario wrestlers (Tommy Nelson, Al Korman, and Ken "Tiger" Tasker). The four-year tour resulted in a fractured shoulder and numerous broken ribs, but it was here that he began to wrestle using the the alias Billy Watson, and thereafter primarily under the name Whipper Billy Watson. Over the course of his career he would also wrestle using the names Billy Potts, Billy Watson, Whipper Watson, and Whooper Watson; ultimately legally changing his name to William John Watson in 1960. His wrestling persona was often found to be on the "good" side, and Watson's trainer Phillip Lawson urged him to cultivate this image through public appearances and carrying himself in a manner that would encourage the admiration of impressionable youngsters, a persona that reports indicate required no deviation from his natural personality. After his initial four years overseas, he returned to Canada and began working with Maple Leaf Wrestling, making his debut on October 3, 1940, marking the start of a thirty-plus year year career in North America. Watson wrestled primarily for promoters Maple Leaf Wrestling and National Wrestling Alliance (with which he had a financial stake with Frank Tunney), he also performed with outfits such as American Wrestling Association, Wildcat Wrestling, St. Louis Wrestling Club, Sam Mchnick Sports Attractions, and Big Time Wrestling, During his career, Watson performed in single and in tag-team matches and faced over 400 different opponents that included Gene Kiniski (234 matches), Ivan Kalmikoff (107 matches), Frtiz Von Erich (91 matches), Killer Kowalski (88 matches), and Buddy Rogers (22 matches), and had more than 130 different partners. He wrestled professionally for what would be the last time on November 28, 1971, as he was struck by a car on November 30. Although surgery saved his leg, the affects of the accident meant he could no longer wrestle and was forced to retire.
Outside of the ring, Watson used his profile to become involved with charities, particularly those involving children with physical disabilities (such as the Easter Seals), and travelled across Canada for fundraisers. In addition, in 1965 he ran in the federal general election for the federal Progressive Conservative Party (for which he received an endorsement from wrestling foe Gene Kiniski), but still finished second.
Watson was named to the Ontario Sports Hall of Fame in 1996 and W.J.Watson Public School in Keswick, Ontario is named in his honour .
Watson died on February 4, 1990 in Orlando, Florida.