Glamorgan. County of south Wales. It was part of the Welsh kingdom of Glywysing, but in the 10th cent., under Morgan Hen, became known as Gwlad Morgan, from which the later name is derived. Under the Normans it was converted to the lordship of Glamorgan, and remained a lordship of the march until 1536, when it was made into a shire at the Act of Union with England, with the addition of the lordship of Gower (Gŵyr). In 1974 it was divided into three—South, Mid, and West Glamorgan.

The county consists of three main elements. Blaenau Morgannwg is the coalfield upland, deeply segmented by valleys, of which the Taff and its tributary, the Rhondda, are best known. In contrast, the southern section called Bro Morgannwg, or the vale of Glamorgan, is a low, level plateau of some 200 feet. The third element is the Gower peninsula.

The county was best known for the coalfield and the mining villages strung out along the valleys. The iron and steel industry of the late 18th and 19th cents. developed on the northern outcrop in places such as Merthyr Tydfil, but exhaustion of local iron ores led to a shift to the coast. The ailing British Steel (Corus) plant at Margam in West Glamorgan is the contemporary successor. Coal-mining has virtually ceased. There is only one deep mine operative, but there are extensive opencast operations. Modern industry has collected about the M4 motorway, which crosses the vale, and north of Cardiff, which grew as a port and is now the capital of Wales. The coalfield communities have suffered greatly from unemployment and contain some of the most deprived areas in the UK (e.g. the Cynon valley).

The total population in 1991 was 1,256,462, nearly half the population of Wales. Welsh speaking increased east to west—3.6 per cent in Trowbridge, a ward of South Glamorgan, to 79.1 in Gwaun-cae Gurwen in the west—and also up-valley, south to north—6.3 per cent at Llantwit Major on the coast to 19.3 in Rhigos, a ward on the northern boundary.

Harold Carter

Glamorgan, kingdom of. A medieval Welsh kingdom which emerged from an earlier kingdom called Morgannwg that covered most of south-east Wales. It may be equated with the post-Roman kingdom of Glywysing, whose line of kings from Meurig ap Tewdrig lasted until the late 11th cent.; these kings extended their power in the 8th cent. to Gwent and Ergyng (Archenfield) to create Morgannwg, probably named after Morgan ab Arthrwys (died c.665) or Morgan ab Owain ( Morgan Hen, d. 974). Prior to the Norman invasions, there were uneasy relations with Deheubarth and Gwynedd. From the 1090s Robert Fitzhamon and the Normans occupied the lowlands and established a marcher lordship between the rivers Neath and Rhymni called Glamorgan; manors, knights' fees, and feudal sublordships replaced earlier Welsh divisions. The conquest accentuated the division between upland and vale, for descendants of native Welsh dynasties continued in the hills until the early 14th cent., acknowledging the overlordship of Deheubarth and, then, of Gwynedd.

Ralph Alan Griffiths