York South (federal electoral district)

The riding is notable for the 1942 federal by-election in which newly elected Conservative leader Arthur Meighen was defeated in his attempt to win a seat in the House of Commons by the Co-operative Commonwealth Federation's (CCF) candidate (assisted by the Liberals).

The election was a major breakthrough for the CCF, and ended Meighen's attempt to return to politics.

As is suggested by the names of the towns in the riding, the constituency abutted on the city of Toronto's northern border.

As time progressed and the population grew, the riding shrank in size so that it consisted of what was later called the Borough of York in the middle western part of Metropolitan Toronto and some surrounding areas.

This riding elected the following members of the House of Commons of Canada: By-election: On Mr. Cockeram's resignation to allow Arthur Meighen to contest the seat: