The original St Dunstan's Cathedral was built from 1897 to 1907. The present stone structure was built between 1913 and 1919 after a fire destroyed the original cathedral in 1913. It was built in the Gothic Revival architectural style.[2]
In 1929, ten years after its completion, the church was blessed by Pope Pius XI as a basilica. The church remains one of the 27 basilicas in Canada.