Saint Patrick's Basilica is the oldest English speaking Catholic parish in Ottawa. It was founded in 1855, although its development goes back much further. Construction of the present Church began in 1868. The original architect was Augustus Laver of the firm Fuller and Laver, architects of the East and West blocks of the Parliament Buildings.

In the long course of constuction, the original plan was changed considerably. In 1872, the cornerstone was blessed by Bishop Guigues, the first bishop of Ottawa, and laid by Sir John A. Macdonald, the first Prime Minister of Canada.

In 1875, the as yet incomplete building was blessed by Archbishop Duhamel and named for the patron saint of Ireland. The Irish have always played an important part in Saint Patrick's parish and many of its pastors have been of Irish descent.

In the beginning, Saint Patrick's had pastoral care of all English-speaking Catholics in Ottawa and across the river in Hull. Gradually, as the Catholic population increased, new parishes were established and the territory of Saint Patrick's was reduced. Today, it is a downtown parish in a neighbourhood that is commercial as well as residential.

Gothic in style, Saint Patrick's Basilica is made of local stone. It has double aisles and a short transept. It seats one thousand people.

A complete history of St. Patrick's Basilica has been published in book form entitled "Enduring Faith, A History of Saint Patrick's Basilica Parish, Ottawa 1855-2005", with many historical pictures and beautiful colour plates. This large hardcover book is available in the Basilica Gift Shop.