The Diocese of Hamilton was established on February 29, 1856 by Pope Pius IX as a division of the Archdiocese of Toronto.  The first Bishop was the Right Reverend John Farrell; installed on May 24, 1856.

The Hamilton Diocese has grown to become the second largest English-speaking Roman Catholic Diocese in Canada, encompassing the Counties of Brant, Bruce, Grey, Halton, Waterloo, Wellington, and four Townships in the County of Dufferin.

There are currently 119 parishes in the Diocese, with the inspiring Christ the King Basilica, built in 1933, as the Cathedral. The Diocese of Hamilton has flourished through the leadership of its Bishops and the faith of its clergy, religious communities, and dedicated parishioners.

The Diocese is proud to celebrate its rich history and cultural diversity.