In 1937, nearly 400 men were employed at the Canadian Malartic, Sladen, and East Malartic mines. Employees doubled during the following year.
According to 1941 statistics, almost 600 of the 2895 Malartic citizens were European immigrants. They were called Fros (foreigners) and their mining experience was invaluable. Ethnocultural groups in the city were comprised of French Canadians, Irish, English, Scottish, Italians, Polish, Russians, Hungarians, Chinese and Yugoslavs.
In 1950, Malartic became the 3rd largest urban centre in the region. According to the 1951 federal census, the total population of Malartic was 5,983.