Between 1921 and 1931, the city’s population grew from 619,000 to 819,000. The population on the Island reached a million people.

In this ever-expanding city, new neighbourhoods swelled with thousands of homes. An efficient tramway system brought workers to their jobs and housewives to commercial thoroughfares, mainly Rue Saint-Catherine. New skyscrapers modeled on American style architecture altered the landscape. Construction began on educational institutions and hospitals.

The 1920s were characterized by an increasing concentration of financial power, which restricted most French-speaking business owners to small and medium-sized ventures.

White-collar workers formed a new social entity, which grew exponentially. Thousands of clerks, secretaries, telephone operators and accountants transformed Montréal’s labour force, previously characterized by its large working class.