COWBRIDGE, a market town and a municipal and contributory parliamentary borough of Glamorganshire, Wales, with a station on the Taff Vale railway branch from Llantrisant to Aberthaw on the coast, distant by rail 1621/2 m. from London, 12 m. W. of Cardiff, 7 m. S.E. of Bridgend, and 6 m. S. of Llantrisant station. The population in 1901 was 1202, a decrease of over 12% since 1891. Less than one-third of the number was Welsh-speaking. The town mainly consists of one long street running east and west, and is in a wide valley through which runs the river Thaw (Welsh, Ddawan), here crossed by a stone bridge.

Cowbridge is probably situated on the Roman road from Cardiff westwards, which seems to have kept nearly the course of the present main road. Roman coins have been discovered here. It has in fact been suggested, mainly on etymological grounds, that the town occupies the site of the Roman Bovium: the modern Welsh name, y Bontfaen (“stone bridge”) is probably a corruption of the medieval, Pont y fôn, the precise equivalent of “Cowbridge,” which is first found in documents of the second half of the 13th century as Covbruge and Cubrigg. Others place Bovium on a vicinal road, at Boverton near Llantwit Major, about 6 m. to the south near the coast, though the most likely site is near Ewenny, 5 m. to the west of Cowbridge. After the Norman conquest of Glamorgan, the town grew up as an appanage of the castle of St Quentin, which occupies a commanding position half a mile south-west of the town. It was walled round before the 13th century. A tower is mentioned in 1487 when it was granted away by the burgesses. Leland in his itinerary (c. 1535) describes the town wall as three-quarters of a mile round and as having three gates. There was even then a considerable suburb on the west bank of the river and outside the walls. The south wall and gateway are still standing.

The town was a borough by prescription until 1682, when it received a charter of incorporation from Charles II. confirming its previous privileges. Under the Unreformed Corporations Act of 1883 the corporation was dissolved, but on the petition of the inhabitants a new charter was granted in March 1887. During the Tudor and Stuart periods Cowbridge was almost if not quite the chief town of Glamorgan, its importance being largely due to its central and accessible position in a rich agricultural district where a large number of the county gentry lived. The great sessions were held here alternately with Cardiff and Swansea from 1542 till their abolition in 1830, and the quarter sessions were held here once a year down to 1850. From 1536 to 1832 it was one of the eight contributory boroughs within the county which returned a member to parliament, but since 1832 it has been contributory with Cardiff and Llantrisant in returning a member. It has a separate commission of the peace. Sir Edward Stradling (1529–1609) established a grammar school here, but died before endowing it; it was refounded in 1685 by Sir Leoline Jenkins, who provided that it should be administered by Jesus College, Oxford, which body erected the present buildings in 1847. It has throughout its existence been one of the leading schools in Wales. An intermediate school for girls was established here by the county in 1896. The church of St Mary (formerly chapelry to Llanblethian) is of early English style and has a fine embattled tower, of the same military type as the towers of Llamblethian and Ewenny. There are three Nonconformist chapels. There are a town hall and market place. The town is now wholly dependent on agriculture, and has good markets and cattle fairs, that on the 4th of May being a charter fair.