This fonds principally contains records connected with the Congregation of St. Basil (Basilian Fathers) whose members administered Assumption College and Assumption University from 1870 onward. Secondarily, it contains varied records that document the history of Assumption and its evolution over time. Included are legal documents, memos, correspondence, ephemera, constitutions and rules, historical narratives and memoirs, reports, and a variety of Basilian publications and formal histories of Assumption. Some items pertain to Catholic education broadly, or to the history of the Catholic Church in Southwestern Ontario. Of special note are Assumption fight songs and a victory song, and the Second World War war diary of Rev. Mike Dalton, a military chaplain.