The first white settlers, six in number, settled as squatters on the land in the late 19th century and were discovered during the survey of the township in 1908. Real colonization began at the time when the National Transcontinental Railway running through the Abitibi region was completed. The first permanent pioneer family arrived in 1912, followed by more settlers and development drawn to the area for its mining, forestry, and agricultural potential, and resulted in the formation of the settlement. In 1915, the post office opened, and a year later, the La Sarre Township was proclaimed, named after the La Sarre Regiment that was recognized for its part in the Battle of Carillon and the capture of Fort Oswego. In 1917, the Township Municipality of La Sarre was established, the same year as the Parish of Saint-André-de-la-Sarre. The Hudson's Bay Company opened a post in 1932, and only operated until 1941.