Dennison (1905-81), a member of the Co-operative Commonwealth Federation, and won a seat in the 1943 provincial election as the Ontario CCF MPP representing St. David electoral district in downtown Toronto. He defeated PC candidate Roland Michener, future Governor General. Dennison was an early environmentalist who tried to stop de Haviland aircraft from polluting Black Creek, tried to force the government to stop a pulp and paper mill from polluting the Spanish River and personally planted 40,000 trees in 1946. Michener defeated Dennison in the 1945 provincial election but Dennison regained the seat in 1948. He lost his seat for the last time during the Conservative sweep that left the Ontario CCF with only two seats in 1951. He was Mayor of Toronto from 1967 to 1972.
