GULF OF ST. LAWRENCE, DIOCESE OF. – A city and diocese in Canada, formerly an apostolic prefecture from 29 May 1882 and an apostolic vicariate from 12 September 1905. The diocese was established by Pope Pius XII with the apostolic constitution *Ad Christi fidelium bonum* of 24 November 1945.
The diocese extends northward to the borders of the Apostolic Vicariate of Labrador, namely to their intersection with the 53rd parallel, and thence westward to the 70th meridian.
To the south, it is bounded by the Saguenay and St. Lawrence Rivers as far as Natashquan, including Antioch Island. To the east, it reaches Natashquan; to the west, the 70th meridian as far as the Saguenay River. It covers approximately 162,975 sq. km. with a population of about 30,000, of whom 29,505 are Catholics, mostly French-speaking. There are 25 parishes, 24 stations, 25 churches, 20 chapels, 21 diocesan priests and 19 religious priests, 3 male religious communities and 5 female religious communities, and a seminary (1949). The cathedral is dedicated to St. John Eudes. The diocese is a suffragan of Rimouski.