Canada has had six main classes of submarines, starting in 1914 with the acquisition of CC1 and CC2. They were replaced by CH14 and CH 15 in 1921. The CH's were in commission only a couple of years between the wars.
Next up were two German U-boats that surrendered in May 1945 on the conclusion of the bloody Battle of the Atlantic. U-889 and U-190 were commissioned in the RCN for a short time.
HMCS Grilse was a former USN Balao class boat; she was leased for a five year period starting in 1961. She was followed by HMCS Rainbow, purchased from the United States in 1968.
Overlapping Rainbow's service on the west coast were Canada's three Oberon-class boats in the Atlantic. Ojibwa was the first, commissioned in September 1965. The O-boats were in service until near the turn of the century.
Canada's four Victoria-class boats are currently serving with two on each coast. The first, HMCS Victoria, was commissioned in the RCN in December 2000; they should be in service for at least another twenty years.
Subsequent posts will deal with each of Canada's classes of boats in more detail.