Major professional sports leagues in the United States and Canada to compete, with the provision that the Stanley Cup winners were to be recognized as "World's Champions". The phrase was repeatedly engraved on the Cup, and continued to be used, when the NHL began admitting American franchises. When the NHL assumed formal control of the Cup in 1947, the resulting agreement required "that the winners of this trophy shall be the acknowledged World's Professional Hockey Champions" (in contrast to the IIHF's Ice Hockey World Championships, at the time contested only by amateurs). When the World Hockey Association commenced play in the 1970s, they sought to challenge for the Stanley Cup,
Edinburgh Trophy of Canada. On the sides of the base, there were small plaques to inscribe the winning team's name. The winners were to be considered the "World's Minor Professional Champions". At the same time, the terms of the championship were announced. The two leagues would play off annually, alternating in the east and the west. The first playoff would be held in the city of the champion of the Western Hockey League. All contested series were best-of-nine format. Edinburgh Trophy The Edinburgh Trophy was a trophy given to the winners of a series played between the champions of the Western Hockey