The question of what happened to the airlines which formed Canadian Airlines has been asked a few times, but has been given somewhat of an incomplete response. So, I'll describe a bit about the airlines that formed Canadian Airlines, and a bit about the merger sequence that brought it together. This info is what I remember from various books, and other resources on the subject, or about the predecessor airlines, and while it may not be 100% correct, as I may misremember some dates and sequences, but it is a reasonable approximation for your understanding. First about the airlines:
Canadian Pacific Airlines: also known as CPAir. Remembered for its 1967-1986 orange livery, of which I have a model right beside me. Yes, in 1986 it did change to something similar to the Canadian Airlines livery that is now being changed. CPAir was formed in 1942 by a buyout and merger of several small, mostly bankrupt bush airlines, and was built into an international carrier. It was owned by Canadian Pacific Limited, one of the largest companies in Canada, and the parent company of the Canadian Pacific Railway. CPAir was seen as a private industry competitor to Air Canada (operated as a subsidiary of CN Rail until 1977), but Canadian Pacific did enjoy a certain amount of its own protection, as CP was a major company with good political connections. CP operated a variety of aircraft over time (including 727, 737-300, 747, DC-8), but by the time of the merger it settled on standardized 737-200 and DC-10-30 aircraft. Although Canadian Pacific loved the idea of owning an airline, they could earn more money by investing in a dozen railway locomotives instead of a DC-10. It was headquartered in Vancouver.
Pacific Western Airlines: known as PWA. Formed in about 1953 in British Columbia, it operated regional routes, flew cargo, and operated in the arctic for many years. It was designated during the regulated era as the regional airline for western Canada in the area west of Calgary. It was owned by the Government on Alberta for a few years, and its head office was moved to Calgary, where it remained. Before the merger PWA had a fleet of 24 737-200's and 2 767-200's. As a note, these aircraft were owned by PWA, and PWA used a sale-leaseback agreement to finance the merger. They had a blue belly on an otherwise white aircraft, with a < sort of logo on the tail in red. I still remember seeing their 737's in Calgary as a kid.
Eastern Provincial Airlines. EPA operated in Eastern Canada. I can't tell you much about them other than they flew some 737's.
Nordair. I believe they were based in Hamilton. They flew 737's in passenger and combi versions, and were the designated regional carrier for Ontario and parts of the Canadian Arctic. Also, they owned (but not 100%, I believe) a commuter airline called Nordair Metro.
Quebecair. Again, not much I know about them, but I can say that at some point they flew BAC-1-11's. They were the regional airline for Quebec.
Transair. Transair was based in Winnipeg, flew 737's and was the designated regional for the area east of Calgary and west of Toronto. They also flew some services into the north.
Calm Air. Based in Thompson, Manitoba, they still operate today as a connector for Canadian Airlines, and are 45% owned by Canadian. Currently operating Saab 340's and HS748's into western Ontario, Saskatchewan, and in Manitoba and Nunavut.
Time Air. Based in Lethbridge, Alberta. A commuter airline which eventually became part of Canadian Regional.
Norcanair. Saskatoon based regional carrier, I believe mostly operating in Saskatchewan and remote areas. All I know is that I have a photo of an F28 in their livery somewhere in the mid '80's.
Wardair. Edmonton based charter airline, operated A310's, also had operated 727's, 707's, DC-10's. It went scheduled shortly before it was merged into Canadian airlines.
Here's the sequence of events leading into the merger. First, in 1978 Transair was bought out by PWA. Effectively this made them somewhat of a national carrier for a while, and they operated as Air Canada's western connector. In about 1985 CPAir purchased Nordair. Then, in December 1986 PWA bought out CPAir, EPA, and I believe Quebecair. This formed Canadian Airlines International Limited, and was financed by the above noted leaseback transaction PWA underwent. PWA remained as the parent company until it was renamed Canadian Airlines Corporation in the mid-90's. At this point I believe acquisitions of Calm Air, Time Air, and some other small airlines also occurred, which were slowly formed into Canadian Regional Airlines. The final stage in the merger process was the purchase of Wardair in 1989. Wardair was originally to be operated as a separate charter arm, but after about a year the Wardair name died and it was fully merged into Canadian Airlines.
I believe Air Atlantic, an eastern regional airline, as well as I believe there existed an Ontario Regional Airlines back then, were also purchased, but I'm not totally sure how they were organized into the merger, but I believe they became part of the company.
I hope that helps folks figure it all out. If you've got questions, please ask, I'm not sure I can answer them, but I can try. Also, any corrections to this. Or for that matter additions? These are the airlines I remember or have read as being part of the merger, it may not be a complete list.
As a side note, I remember when the merger happened. My neighbor worked for PWA, and he brought me a whole bunch of the leftovers when the changed the name. He had a ramp parka with CPAir on it, I got a DC-10 model in the old CPAir orange, and he had a whole pile of PWA and later Wardair envelopes and stationary. There was other stuff too, I wish I had gotten some of that stuff. I can also remember the editorial cartoons when the smaller PWA purchase CPAir, and there were cartoons of PWA airplanes having just eaten CPAir, and the caption I remember was "I can't believe I ate the whole thing." I also remember when they bought Wardair, and seeing A310's in Wardair colours with the Canadian Airlines name painted on them.