Monmouth Castle

Immediately after the Norman Conquest, William the Conqueror installed three of his most trusted confidants — Hugh d'Avranches, Roger of Montgomery and William FitzOsbern — as Earls of Chester, Shrewsbury and Hereford, earldoms that guarded the frontier and served as bases for the Norman push into Wales. FitzOsbern established Monmouth Castle between 1066 and 1069 as a counterpart to his other major castle at Chepstow, on relatively high ground overlooking the confluence of the Monnow with the River Wye.

It began as an earth and timber ringwork, listed in the Domesday Book of 1086, with stonework added before 1150; its tower shares some similarities with that of Chepstow, FitzOsbern's stronghold at the lower end of the Wye. In these years Monmouth was a fairly typical border castle of the Welsh Marches, presided over by a Marcher lord and similar in style and status to its near neighbours Grosmont, Skenfrith, White Castle and Abergavenny.

After briefly being held by Simon de Montfort, Earl of Leicester, the castle passed in 1267 to Edmund Crouchback, Earl of Lancaster and son of Henry III, who built the Hall and took Monmouth as his main residence in the area. Further improvement came in the early fourteenth century, probably under Crouchback's grandson Henry of Grosmont, 1st Duke of Lancaster, when large decorated windows were set into the upper part of the Great Tower beneath a new roof. As the town grew around the castle, its defences were augmented at the end of the thirteenth century by a town wall and a fortified bridge.

The castle brushed against the fate of kings more than once. Edward II was briefly held prisoner here before his transfer to Berkeley Castle, where he died. It became a favourite residence of Henry Bolingbroke, the future Henry IV, and in 1386 his first wife Mary de Bohun gave birth in the castle to the future Henry V.

The decade of the Owain Glyndŵr rebellion never directly touched Monmouth Castle: it was a stronghold of the region, and lesser targets offered themselves more readily to what was essentially a guerrilla army. Its neighbours fared worse — Grosmont and Abergavenny were razed, and Crickhowell and Newport castles successfully attacked.

As its defensive purpose faded, the outer bailey became a market place, later known as Agincourt Square. When Monmouth became the county town of the newly formed shire in the sixteenth century, the county's Courts of Assize began sitting in the castle's Great Hall.

In the English Civil War the castle changed hands three times, finally falling to the Parliamentarians in 1645. Oliver Cromwell visited Monmouth in 1646 and, by tradition, ordered the castle's slighting; on 1 March 1647 the House of Commons resolved 'That the Town and Castle of Monmouth be disgarisoned, and the Works slighted'. Demolition began with the round tower on 30 March 1647 and dragged on for months. More Pye, then usher at Monmouth School, recorded the end in his diary: on 22 December 1647, 'about twelve o'clock, the Tower in the Castle of Monmouth fell down, upon one side, whilst we were at sermon'.

By the end of the eighteenth century William Gilpin, passing through on his Wye Tour, could mock what remained: 'formerly the palace of a king, and birth-place of a mighty prince: it is now converted into a yard for fatting ducks'.

In 1673 Henry Somerset, 1st Duke of Beaufort, built Great Castle House on the site of the demolished round tower; the Assize Courts sat there until they moved to the new Shire Hall in 1725. In 1875 the Royal Monmouthshire Royal Engineers Militia — today the senior Army Reserve regiment — made it their headquarters, and it remains so, making Monmouth one of the few British castles in continuous military occupancy, with the regimental museum housed in the stable block. The surviving fragments — the Great Tower and Hall and parts of the walls — are a Grade I listed building and scheduled monument in the care of Cadw.