The status does not apply automatically on the basis of any particular criteria, although in England and Wales it was traditionally given to towns with diocesan cathedrals. This association between having a cathedral and being called a city was established in the early 1540s when King Henry VIII founded dioceses (each having a cathedral in the see city) in six English towns and also granted them city status by issuing letters patent.
City status in Ireland was granted to far fewer communities than in England and Wales, and there are only two pre–19th-century cities in present-day Northern Ireland. In Scotland, city status did not explicitly receive any recognition by the state until the 19th century. At that time, a revival of grants of city status took place, first in England, where the grants were accompanied by the establishment of new cathedrals, and later in Scotland and Ireland. In the 20th century, it was explicitly recognised that the status of city in England and Wales would no longer be bound to the presence of a cathedral, and grants made since have been awarded to communities on a variety of criteria, including population size.
The abolition of some corporate bodies as part of successive local government reforms, beginning with the Municipal Corporations (Ireland) Act 1840, has deprived some ancient cities of their status. However, letters patent have been issued for most of the affected cities to ensure the continuation or restoration of their status. At present, Rochester and Elgin are the only former cities in the United Kingdom. The name "City" does not, in itself, denote city status; it may be appended to place names for historic association (e.g. White City) or for marketing or disambiguation (e.g. Stratford City). A number of large towns (such as with over 200,000 residents) in the UK are bigger than some small cities, but cannot legitimately call themselves a city without the royal designation.
The initial cities (Latin: civitas) of Britain were the fortified settlements organised by the Romans as the capitals of the Celtic tribes under Roman rule. The British clerics of the early Middle Ages later preserved a traditional list of the "28 Cities" (Old Welsh: cair) which was mentioned by Gildas and listed by Nennius.
In the 16th century, a town was recognised as a city by the English Crown if it had a diocesan cathedral within its limits. This association between having a cathedral and being called a city was established when Henry VIII founded dioceses (each having a cathedral in the see city) in six English towns and also granted them city status by issuing letters patent. Some cities today are very small because they were granted city status in or before the 16th century, then were unaffected by population growth during the Industrial Revolution—notably Wells (population about 10,000) and St David's (population about 2,000), After the 16th century, no new dioceses (and no new cities) were created until the 19th century.