Yamaska is a municipality in the Pierre-De Saurel Regional County Municipality, in the Montérégie region of Quebec. The population as of the Canada 2011 Census was 1,644.DemographicsPopulationPopulation trend: Amalgamation of Parish of Saint-Michel-d’Yamaska and the Villages of Yamaska and Yamaska-Est.LanguageMother tongue language (2006)