The day after his ordination, François-Xavier Fafard went to St. Claude Misson, on the Ontario side of Lake Temiskaming. He arrived there on March 29, 1885, which was Palm Sunday.
As soon as he arrived, Father Fafard went to work. He preached the Gospel to Native people,and travelled to logging camps to provide spiritual assistance to lumberjacks. It took several days to go from one place to the next in those days. Snowshoes and canoes were the usual means of transportation
In 1886, St.Claude Mission was moved to the location now called Ville-Marie, which was then named Baie-des-Pères. François-Xavier was responsible for the construction of church, a rectory presbytery, and hospilal.
In 1888, he built a small chapel at Tête-du-lac, which became later Notre-Dame-du-Nord. He also played a role in the establishment of the parishes of Lorrainville, Fabre, Guigue, and Laverlochère.