Until 1974, Denbighshire, or the County of Denbigh, was an administrative county in the north of Wales, later classed as one of the thirteen historic counties of Wales. It was a maritime county, that was bounded to the north by the Irish Sea, to the east by Flintshire, Cheshire and Shropshire, to the south by Montgomeryshire and Merionethshire, and to the west by Caernarfonshire.

Until 1974, Montgomeryshire was an administrative county in mid Wales, later classed as one of the thirteen historic counties of Wales. It was named after its county town, Montgomery, which in turn was named after one of William the Conqueror's main counsellors, Roger de Montgomerie, who was the 1st Earl of Shrewsbury.