Westminster Cathedral
The site on which the cathedral stands in the City of Westminster was purchased by the Diocese of Westminster in 1885, and construction was completed in 1903. Westminster Cathedral is the largest Catholic church building in England and Wales and the seat of the Archbishop of Westminster.
Diocese of Westminster (Church of England)
The Diocese of Westminster was a short-lived diocese of the Church of England, extant from 1540–1550. Westminster Abbey served as its cathedral.