Montreal was one of the cities in Quebec affected by the 2000–2006 municipal reorganization in Quebec. On January 1, 2002, all the municipalities on the island of Montreal were merged into the city of Montreal.
However, following a change of government in the 2003 Quebec election and a 2004 referendum, some of those municipalities became independent cities again on January 1, 2006. The recreated cities did not regain all of their previous powers, however. A new urban agglomeration of Montreal was created, which resulted in the recreated cities still sharing certain municipal services with Montreal.
Until 2001, the island of Montreal was divided into the city of Montreal proper and 27 smaller municipalities. These formed the Montreal Urban Community (MUC). On January 1, 2002, all 28 municipalities on the island were merged into the "megacity" of Montreal, under the slogan "Une île, une ville" ("One island, one city"). This merger was part of a larger provincial scheme launched by the Parti Québécois all across Quebec, resulting in the merging of many municipalities. It was felt that larger municipalities would be more efficient, and would be more able to withstand comparison with the other cities in Canada, which had already expanded their territory--most notably Toronto, which had merged with the other municipalities in Metro Toronto in 1999 (the GTA is a regional area including Toronto and the surrounding cities).
As happened elsewhere in Canada, the merger was opposed by many residents on the island of Montreal. The situation on the island of Montreal was further complicated by the presence of predominantly English-speaking municipalities that were due to merge with the predominantly French-speaking city of Montreal. English speakers were afraid to lose their rights, despite claims by the mayor of Montreal that their linguistic rights would remain protected in the new city of Montreal. Many street protests were organized, lawsuits were filed, 15 municipalities appealed to the Court of Appeal of Quebec, but it was all to no avail. At the 2001 census, the city of Montreal (185.94 km²/71.80 sq. miles) had 1,039,534 inhabitants. After the merger, the population of the new city of Montreal (500.05 km²/193.10 sq. miles) was 1,812,723 (based on 2001 census figures). The post merger city was 169% larger in terms of land area, and had 74% more people. For comparisons, at the 2001 census the city of Toronto (629.91 km²/243.20 sq. miles) had 2,481,494 inhabitants.