Vale of Glamorgan

Prior to 1974 the area was part of the county of Glamorgan or Glamorganshire. Between the 11th-century and 1536 the area was part of the Lordship of Glamorgan.
In medieval times, the village of Cosmeston, near what is today Penarth in the south east of the county, grew up around a fortified manor house constructed sometime around the 12th century by the De Costentin family. The De Costentins, who originated on the Cotentin peninsula in northern France, were among the first Norman invaders of Wales in the early 12th century following William the Conqueror's invasion of neighbouring England in 1066. The village would have consisted of a number of small stone round houses, or crofts, with thatched roofs.
Clemenstone, to the west, was the seat of several high sheriffs of Glamorganshire, including John Curre who was known have occupied the estate in 1712. William Curre, known to have lived in Clemenstone in 1766, was also an occupant of Itton Court in Monmouthshire. In the early 19th century, Lady Sale née Wynch, wife of Sir Robert Sale, spent much of her early life on the Clemenstone Estate.
In 1974, the area became part of South Glamorgan, under the Local Government Act 1972. It created several problems in local governance, between the South Glamorgan County Council, Cardiff City Council and the Vale of Glamorgan Borough Council owing to their conflicting interests. It was a turbulent time for governance in the city of Cardiff, as for the first time in its history it had to share authority with the county council, which was larger and better resourced. In April 1996, the Vale of Glamorgan became a county borough (unitary authority) of Wales, after forming part of South Glamorgan county.