Union municipale de Saint-Léonard
The UMSL was formed prior to the 1982 municipal election, in which it fielded Jean Desjardins as its mayoral candidate and a full slate of twelve candidates for city council. Desjardins finished second against incumbent Antonio di Ciocco of the governing Équipe du renouveau de la cité de Saint-Léonard. Two of the UMSL's candidates, Tommaso Nanci and Remi Borger, were returned to council.
Rosario Ortona became the UMSL's leader after the 1982 election and was its mayoral candidate in a 1984 by-election that was called after di Ciocco's unexpected death. He finished third against Raymond Renaud of the newly formed Ralliement de Saint-Léonard. The UMSL also contested an April 1985 by-election, with a candidate who was narrowly defeated by a member of Renaud's party.
Nanci and Borger resigned from the UMSL in July 1985 to sit as independents, saying that they intended to form a new party that would better represent Saint-Leonard's merchant community. Ortona criticized this decision, saying that they could have pursued the same goal within the UMSL. Nanci and Borger subsequently joined the Unité de Saint-Léonard party while Ortona ultimately dissolved the UMSL to join the Rassemblement des citoyens et citoyennes de Saint-Léonard. All three were defeated by candidates of Renaud's party in the 1986 municipal election.
- Le Journal de Saint-Léonard, 9 November 1982, pp. 2-4.
- "Plan to shut elementary main issue in election," Montreal Gazette, 17 April 1985, p. 3; "Ruling party's candidate wins St. Leonard seat," Montreal Gazette, 24 April 1985, p. 1.
- "Two St. Leonard councillors quit to organize new opposition party," Montreal Gazette, 17 July 1985, p. 1.
- "Montreal North, St. Leonard show different election styles," Montreal Gazette, 20 October 1986, p. 4.