Through Cutler and Kartje, Caddock was introduced to
Frank Gotch and
Martin 'Farmer' Burns who began to train him for Professional wrestling. On June 8, 1915, Earl Caddock made his professional debut in a match against Jesse Westergaard. His popularity grew and on April 19, 1917, he defeated
Joe Stecher for the
World Heavyweight Championship in
Omaha, Nebraska. In December 1917 a tournament was held with the winner to be declared World Heavyweight Champion. Caddock walked out of this tournament over promoter
Jack Curley's refusal to bill him as World Heavyweight Champion.
Władek Zbyszko won the tournament and was declared the new World Heavyweight Champion. The appetite for a match between Caddock and Zbyszko was fierce and on February 8, 1918, it happened. The result was predictable with Caddock once again becoming World Heavyweight Champion. In August of that year his wrestling career was temporarily put on hold for his service in the
First World War. Caddock was discharged from the Army on June 1, 1919, and he returned to his career in wrestling. The World Heavyweight Championship had changed hands a few times while he was at war and was once again held by Joe Stecher. A match between the two was immediately set. On January 30, 1920, fans packed
Madison Square Garden to see Stecher defeat Caddock. This match was filmed by pioneer cinematographer
Freeman Harrison Owens, and is currently the oldest surviving filming of a professional wrestling match. Caddock's career continued successfully for the next few years but he wouldn't be in another World Title match until 1921. In January of that year Caddock faced
Ed "Strangler" Lewis for the championship. Caddock's loss to Lewis in this match resulted in a near riot. Another title match in November against
Stanislaus Zbyszko resulted in another failure to recapture the World Heavyweight Championship. Earl Caddock's final match took place on June 7, 1922. He lost his last bid to regain the World Heavyweight Title to Ed Lewis. ==Retirement from pro wrestling==