Cardiff was recognised as the capital of Wales by the British government.

Cardiff is the capital and largest city of Wales. Cardiff had a population of 372,089 in 2022 and forms a principal area officially known as the City and County of Cardiff. The city is the eleventh largest in the United Kingdom. Located in the southeast of Wales and in the Cardiff Capital Region, Cardiff is the county town of the historic county of Glamorgan and in 1974–1996 of South Glamorgan. It belongs to the Eurocities network of the largest European cities. A small town until the early 19th century, its prominence as a port for coal when mining began in the region helped its expansion. In 1905, it was ranked as a city and in 1955 proclaimed capital of Wales. The Cardiff urban area covers a larger area outside the county boundary, including the towns of Dinas Powys and Penarth.

The current capital of Wales is Cardiff. Historically, Wales did not have a definite capital. In 1955, the Minister for Welsh Affairs informally proclaimed Cardiff to be the capital of Wales. Since 1964, Cardiff has been home to government offices for Wales, and since 1999 it has been the seat of the Senedd.