NHL–WHA merger

The 1979 merger of the NHL and WHA was the culmination of several years of negotiations between the National Hockey League (NHL) and the World Hockey Association (WHA) that resulted in four WHA franchises, the Edmonton Oilers, New England Whalers, Quebec Nordiques, and Winnipeg Jets joining the NHL for the 1979–80 season. The agreement ended the seven-year existence of the WHA and re-established the NHL as the lone major league in North American professional ice hockey.

The two leagues had discussed the possibility of merging for numerous years, despite the acrimonious relationship between the two after the WHA aggressively recruited NHL players upon the former's founding in 1971. The two sides came close to an agreement in 1977, but the merger was defeated by a group of hard-line NHL owners. The NHL also initially rejected the 1979 agreement by one vote. However, a massive boycott of Molson products in Canada led the Montreal Canadiens, who were owned by the Molson family, to reverse their position in a second vote along with the Vancouver Canucks, allowing the plan to pass.

As part of the agreement, the NHL treated it more as an expansion rather than an outright merger. The former WHA clubs were stripped of most of their players and permitted to keep only two goaltenders and two skaters, and NHL teams were given the right to reclaim players from the WHA clubs without compensation. The four former WHA teams were also placed at the end of the draft order for the 1979 NHL Entry Draft, as opposed to previous NHL expansion teams, which had been placed at the front of the draft order.

Since the demise of the Western Canada Hockey League in 1926, the NHL had existed as the only major professional North American ice hockey league. After dwindling to the Original Six in 1942, the NHL remained stable until the 1960s. Following speculation that the Western Hockey League intended to declare itself a major league, the NHL was entertaining serious expansion discussions by 1963, culminating four years later with the addition of six new teams for the 1967–68 NHL season.

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