The Ontario Rugby Football Union or ORFU was an early amateur Canadian football

Canadian football

Canadian football is a form of gridiron football played exclusively in Canada in which two teams of 12 players each compete for territorial control of a field of play long and wide attempting to advance a pointed prolate spheroid ball into the opposing team's scoring area...

 league with teams in the Canadian

Canada

Canada is a North American country consisting of ten provinces and three territories. Located in the northern part of the continent, it extends from the Atlantic Ocean in the east to the Pacific Ocean in the west, and northward into the Arctic Ocean...

 province of Ontario

Ontario

Ontario is a province of Canada, located in east-central Canada. It is Canada's most populous province and second largest in total area. It is home to the nation's most populous city, Toronto, and the nation's capital, Ottawa....

. The ORFU was founded in 1883 and in 1903 became the first major competition to adopt the Burnside Rules

Burnside Rules

The Burnside rules were a set of rules that transformed Canadian football from a rugby-style game to the gridiron-style game it has remained ever since...

, from which the modern Canadian football code would evolve.

During the Second World War, the military teams in Ontario played in the ORFU filling the gap during the suspension of play by the Interprovincial Rugby Football Union

Canadian Football League East Division

The East Division is one of the two regional divisions of the Canadian Football League. Although the CFL was not founded until 1958, the East Division and its clubs are descended from earlier leagues.- Pre-1907 :...

.