Joseph was born 1854 in Frenchville, Maine. He married Marguerite Violette at St Bruno's Church, Van Buren Maine on 9 Feb 1872. They had 11 children and Maggie died in childbirth with her 12th child. Joseph married Eugenie Plante on 27 Sept, 1898 at St John the Baptist Church in Dayton, MN. They had 3 more children. After Eugenie died, Joseph married for the third time to Helen Beaudoin on 26 Jan 1911; at St Joseph Church, Dickinson, Stark Co, Minnesota. Joseph's parents were Benjamin Levasseur and Adelaide Marquis. No one knows why Joseph changed the spelling of his surname to Vassar when he and Margurite came to Minnesota about 1876 from Frenchville, Maine. According to most legal documents, including censuses and deeds the surname was spelled Vassar. However, St John the Baptist Catholic Church in Dayton, Minnesota, always spelled the surname as Vasseur. To add to the confusion, the births of Prosper in 1877 and Georgiana in 1879, children of Joseph and Marguerite, are listed by the State of Minnesota as Levasseur while Elizabeth born in 1876 is Vassar. Joseph and Marguerite's children: Joseph, Jr., Alfred and Alexander and their descendants, used Vassar. The exception was Prosper and his descendants who changed the spelling of their surname name to Vasseur in the 1920's. Joseph Vassar, Sr. after emigrating to Bonneyville, Alberta, legally changed his and his son's Frederic, Theophile, Archibald and Paul Frank (aka Frank Paul) to Vasseur so all the Canadian descendants spell their surname Vasseur.
Joseph had a farm in Dayton, MN. Joseph was not a farmer, but the soil was perfect for making brick, so he built his house out of the clay from his farm, houses for his hired hands were also on the same property, made of this beautiful golden brick. The Church of St.Michael in St. Michael, Minnesota was also built of the brick made on Joseph's farm. The Church of St. Michael cornerstone was laid in 1890 and is now on the national historic register.