MONMOUTH (Welsh Mynwy), municipal borough, and county town of Monmouthshire, England, 18 m. S. of Hereford, on the G.W. railway. Pop. It is situated at the confluence of the Wye and the Monnow and is almost surrounded by hills. Monmouth (Monemuta) was possibly a " fort from Roman times. Situated between Severn and Wye its strategic importance was early recognized by the Saxons, while in later years it played a leading part in Welsh border warfare. At the time of Domesday the castle was in the custody of William Fitz Baderon. Henry III. granted it to his son Edmund Crouchback, through whose descendants both borough and castle passed into the duchy of Lancaster. Since the 18th century the dukes of Beaufort have been lords of the borough.
Portions of the town walls remain, and there is an old gateway on the Monnow bridge ; but there are only insignificant ruins of the castle, originally a Saxon fortress. The principal buildings
include the churches of St. Mary on an ancient site, and the chapel of St. Thomas, a late Norman structure, and the free gram mar-school, founded in Monmouth was a borough by prescription as early as 1256, and was governed by a mayor in 1461, but was not incorporated until 155o. This charter was confirmed in 1558, 1606 and 1666. By the act of 1535-36 Monmouth, as county town, obtained representa tion in parliament ; it is now part of one of the county divisions. Wednesday and Saturday markets were confirmed to Monmouth in 1550. Since the 18th century it has been a quiet market town deriving some prosperity from the rise of the adjoining industrial regions as well as an annual three-days' fair.