In 1822 St. Paul's was established as the first Roman Catholic Parish between Kingston and Windsor. The first Church, built of red brick, was opened on this site in 1824. The land to the East of the Church was used as Toronto's first Catholic Cemetery.
On December 22, 1889, the present Italian Renaissance-Style Church was dedicated. It was designed by the Architect Joseph Connelly, under the inspiration of the then Pastor, Bishop Timothy O'Mahony. The beauty of the Church enhances its importance as the Mother Church of the Toronto Archdiocese.
On August 3, 1999, Pope John Paul II elevated St. Paul's to Basilica Status.