The Diocese was established by decree in 1987. Formerly a part of Menevia Diocese, it consists of the 6 Counties of North Wales and the district of Montgomery in the County of Powys in Mid-Wales.
There are major population centres throughout the Diocese. To some degree each of the Counties also has sparsely populated rural communities, the proportion of which increases progressively as one travels west.
There are 41 Parishes with 65 churches serving a Catholic population of over 30,000.