In addition to the issues of Quebec sovereignty , a number of crises shook Canadian society in the late 1980s and early 1990s . These included the explosion of Air India Flight 182 in 1985 , the largest mass murder in Canadian history ; the École Polytechnique massacre in 1989 , a university shooting targeting female students ; and the Oka Crisis of 1990 , the first of a number of violent confrontations between the government and indigenous groups . Canada also joined the Gulf War in 1990 as part of a U.S.-led coalition force and was active in several peacekeeping missions in the 1990s , including the UNPROFOR mission in the former Yugoslavia
École Polytechnique massacre
École Polytechnique massacre
Canada