The idea to build the Forum in 1923 is credited to Sir Edward Wentworth Beatty, president of the Canadian Pacific Railway. At the suggestion of Senator Donat Raymond, William Northey developed a plan for a 12,500 seat capacity rink. Plans were scaled back for financial reasons to a rink of 9,300 seats. Even at the reduced size, the rink could not immediately find financing.

The Forum would eventually be financed by H. L. Timmins. The site selected was the site of a roller skating rink named the Forum, and the name was kept.

The site had previously been the site of an outdoor ice Hockey rink, used by Frank and Lester Patrick, Art Ross and Russell Bowie as youths.

The Forum opened on November 29, 1924, at a total cost of C$1.5 million. The original seating capacity was 9,300. It underwent two renovations, in 1949 and 1968. When the Forum closed in 1996 it had a capacity of 17,959, which included approximately 1,600 in standing room.

Originally built for the Montreal Maroons NHL team, The Montreal Forum hosted the Montreal Canadiens for the very 1st ice Hockey game in the arena, as the Maroons were on the road in Boston to start their season, and the Canadiens were unable to use their rink because the natural surface at the Mount Royal Arena was not yet playable.

The Canadiens defeated the Toronto St. Pats 7-1 on November 29, 1924. Billy Boucher scored the 1st goal in the history of the Forum, beating John Ross Roach at 55 seconds of the 1st period. He also scored the next 2 goals in the game, recording the building’s 1st hat trick and 1st natural hat trick. Boucher also had the 1st penalty, a minor in the 1st period.

While hosting the Canadiens and Maroons on Thursdays and Saturdays, the Forum also hosted the Quebec Senior Hockey League / QSHL, featuring the Montreal Victorias, Montreal Royals and the Montreal Canadiens amateur team on Wednesdays and Sundays. The Quebec Junior Hockey League played on Monday nights, the Bank League on Tuesdays and the Railways and Telephone League played on Friday nights.

The Forum hosted the Stanley Cup Finals in 1926, 1928, 1930, 1931, 1944, 1946, 1947, 1951, 1952, 1953, 1954, 1955, 1956, 1957, 1958, 1959, 1960, 1965, 1966, 1967, 1968, 1969, 1971, 1973, 1976, 1977, 1978, 1979, 1986, 1989, and 1993.

Only two visiting teams have ever won the Stanley Cup on Forum ice: the New York Rangers did so in 1928, defeating the Maroons, while the Calgary Flames defeated the Canadiens in 1989.

The Montreal Forum hosted Memorial Cup games in 1950, 1968, 1969, 1970, 1973 & 1976, with the Junior Canadiens winning on home ice in 1970.

On March 11, 1937, the Forum hosted its only funeral, for Canadiens legend Howie Morenz.

Along with one other Original Six indoor ice Hockey arena, the Boston Garden, the Montreal Forum used a high-pitched siren to signal the end of an NHL game's period — the siren would later be re-installed in the Forum's successor facility, the Bell Centre.

On March 11, 1996, the Montreal Canadiens played their last game at the Montreal Forum, defeating the Dallas Stars 4-1.

The building was declared a National Historic Site of Canada in 1997 because - "it was arguably the country's most famous sporting venue... it also serves as an icon for the role of hockey in Canada's national culture... the Forum is the oldest of Canada's large-scale arenas and has, throughout its history, been the country's leading site for major indoor cultural, political and religious events."

"Historic Sites and Monuments Board of Canada, Minutes, June 1997"