 The Grey Cup is one of Canada's largest annual sports and television events.The CFL was officially named on January 19, 1958, upon the merger between the Interprovincial Rugby Football Union or "Big Four" (founded in 1907) and the Western Interprovincial Football Union (founded in 1936).Before the introduction of interlocking play in 1961, teams only competed against each other in pre-season and the Grey Cup Championship (similar to Major League Baseball in the United States).