This fonds provides information on the history of the Fort William Mission and the surrounding area. It contains historical brochures and diaries about the Fort William Mission. It documents the missionary activities of the region. It also provides an account of Jesuit activities with the Indigenous communities in the area, including marriage licenses, lease agreements, and various contracts.

The fonds contains some correspondence of Nicolas Fremiot, S.J., detailing his activities in the region, as well as other correspondence by Jesuit priests involved in the Northern Ontario missions.

The fonds testifies to the activities carried out by the Holy Cross Mission of Wiikwemkoong since its transfer to the Jesuits in 1844 and until 2004, and provides information on the history of Manitoulin Island, Wiikwemkoong and other communities of Northern Ontario. It provides information on the activities of the parishes Jesuit missionaries served via administrative and financial records, as well as sacramental registers that compiled data on the members and families of the communities. Thus, in addition to documenting the activities of the Holy Cross parish and missionaries, the fonds contains records concerning the parishes of Gore Bay, Little Current, Killarney, Batchewana, M’chigeeng, Sheshegwaning, Spanish River and Lake Huron North Shore, among others. It also contains records testifying to the Jesuits’ interest and implication in schools in Batchewana, Kaboni, Killarney, Sheguiandah, Spanish, and Wiikwemkoong.

The fonds contains diaries and notes taken by Jesuit priests concerning the activities of the missions and certain events. It also contains correspondence, parish communications, work documents and history notes, Status Animarum, Historia Domus, manuscripts, two publications, a prospectus, programs, architectural drawings and maps, as weel as photographs that document the different mission points, landscapes, church buildings, Catholic celebrations, events, and parish members and families.