The 1918 Armistice signalled the beginning of a painful period of adjustment: conversion to a peacetime economy, the return of demobilized soldiers, an alarming inflation rate and labour unrest. From 1920 to 1922, a serious economic crisis occurred, combined with a dramatic rise in unemployment. This was the context in which the Québec government adopted the Public Charities Act and the federal government nationalized the railways. The head offices of the two main railways, Canadian Pacific and Canadian National, remained in Montréal.

Post-war tensions could also be felt in municipal politics. The City’s numerous annexations had created a heavy fiscal burden that alarmed bankers. The Québec government placed Montréal under trusteeship from 1918 to 1921.