The Catholic Church in London began before London had a formal diocese, and before the erection of its first basilica. Catholicism was brought to Canada by the Jesuits and other missionary groups to baptize the native population. Generally missionary work was concentrated on the fur trade routes of Canada and in Quebec. Eventually, Catholicism reached Southwestern Ontario in the early 19th century.

   In 1856 the Vatican created the Diocese of London on February 21, 1856, with Pierre-Aldolphe Pinsoneault as its first bishop. Prior to this, a priest administered London from St. Thomas and masses were held at its only Catholic Church, called St. Lawrence the Martyr. In 1885 St. Peter’s Cathedral was established in London, and a few other churches were built between then and World War II. After World War II an influx of European immigrants caused more churches to be built within the London region.

     In the 1960’s the Catholic community in London began to change. Rulings from Vatican II changed the way Londoners worshiped in Catholic churches. Many of the buildings were altered to incorporate these new rulings. Since the 1960’s London’s Catholic community has continued to prosper.

In addition to the religious role of the church, there has also been an educational focus in the London community. The Diocese of London has been responsible for the creation of St. Peter’s Seminary in 1912, Brescia University College in 1919, King’s University College in 1954, as well as various elementary and high schools.