The castle was erected shortly after the Norman invasion of England in 1066, when William the Conqueror set William Fitz Osbern as Earl of Hereford. William enlarged his lands by winning Monmouth and Chepstow, and began building castles there to subdue the Welsh. White Castle, originally called Llantilio, was one of the three strongholds built at that time in the Monnow Valley (the others are Grosmont and Skenfrith). It was to protect the route from Wales to Hereford and to tower over the Monnow River.
When a great Welsh uprising broke out in 1135, king Stephen in response reorganized the border march, bringing White Castle and its sister strongholds in Grosmont and Skenfrith under the control of the Crown, and creating a lordship known as the Three Castles. After a period of peace under the rule of Henry II in the 60s of the twelfth century, in 1182 again fighting broke with the Welshmen. The nearby castle at Abergavenny was almost completely destroyed, which made it necessary to strengthen the defense of White Castle. In the years 1184-1186, the royal official Ralph of Grosmont made works costing 128 pounds, erecting a stone defensive wall and a keep, but the attack did not finally take place.
In 1201 king John gave the Three Castles to Hubert de Burgh. Hubert was a small landowner who became John‘s chamberlain when he was still a prince, and became a powerful royal official when John inherited the throne. He began to modernize his new strongholds, starting with Grosmont, but was captured during fights in France. During his captivity the king handed over the White, Grosmont and Skenfrith castles to William de Braose, rival of Hubert. However, already in 1207, William fell out of royal favors, and his son, also called William, engaged in the so-called First Baron’s War with the king. After the release, Hubert regained power and influence, becoming Earl of Kent and regaining the Three Castles in 1219 during the reign of king Henry III. He ruled them until 1232, when was imprisoned because of the intrigues of his opponents, and White Castle was put under the command of the royal servant, Walerund Teutonicus. Hubert returned to White Castle in 1234-1239, but the sisterly strongholds were finally granted in 1254 to the eldest son of king Henry, prince Edward.
In the 13th century, the castle was significantly rebuilt. It is most often assumed that this took place in the 50s and 60s, but it is also possible to have a slightly earlier dating, during the reign of Hubert, who would carry out the reconstruction in two stages: in the years 1229-1231 and 1234-1239. During this time, the fortifications were first described in the documents as “White Castle”, due to the bright color of its outer walls.
In 1262 the castle was prepared for defense in relation with the attack of the Welsh prince Llywelyn ap Gruffudd on Abergavenny, but the fights for White Castle did not happen. In 1267, Edmund, Earl of Lancaster and commander of the royal forces in Wales, received the Three Castles, which for several centuries belonged to the later Duchy of Lancaster. The conquest of Wales by king Edward I in 1282 caused the castle to lose its military significance. Minor repairs were carried out in the fifteenth century under the reign of king Henry VI, but in 1538 the White Castle ceased to be used, and then fell into disrepair. In the 17th century it was in such a bad condition, that it was not used during the English Civil War.
The castle was erected on a hill near the village of Llantilio Crossenny. Originally it was a timber and earth structure, rebuilt in the second half of the 12th century. Then it received a stone perimeter of defensive walls with an oval shape and dimensions of about 46 by 34 meters. In its south-eastern part, a quadrilateral keep was built, probably adjoining by one side to the defensive wall. The original entrance to the castle was from the south.
In the 13th century, the castle was significantly expanded. The ring of defensive walls was reinforced with four semicircular and cylindrical towers, and the gate, which was located from the north, was made of two, powerful, cylindrical flanking towers. The gate towers had four floors, and the passage was secured by a portcullis, two doors and a drawbridge. The north-eastern tower in the fifteenth century had to undergo significant repair work, probably as a result of partial collapse. The defensive wall and towers were equipped with atypical arrowslits in the shape of crosses, moved vertically so that one side was higher than the other. This setting helped to improve the defender’s field of view. At the inner ward, to the east of the gate, there was a hall building, next in the eastern part a building with private chambers (solar), and a chapel connected with one of the towers. The keep in this period probably did not function anymore (the last known information about its repair comes from 1256). Right next to its remains, there was a side, wicket gate in the southern part of the perimeter. It led to a small bridge over the moat and further to the earth ramparts defending the castle from the south (hornwork). The western side of the inner ward was occupied by the late medieval economic buildings and the kitchen. The outer defense was deep, reinforced with a wall and a water-filled moat. It was controlled by two dams: in the south-east and north-west.
On the north and north-west sides of the castle there was an outer bailey, which stone walls were erected in the 13th century. It had dimensions of about 98 by 52 meters and was reinforced with four towers, three of which were semi-circular, two-story, and one four-sided. The latter probably housed living quarters, because it had a fireplace and a latrine. The castle’s gatehouse was located in the eastern part, next to the moat of the upper castle. It consisted of two flanking towers, protruding from a four-sided gatehouse building. It had a portcullis and a drawbridge over the probably dry moat. Across the outer ward, on its north-western edge, next to a group of smaller, timber buildings, a large house was erected, probably a barn, measuring 35 by 20 meters.
The castle has been preserved in the form of a legible ruin with almost full circumference of the upper castle’s walls (inner ward) and most of the fortifications of the outer bailey. Unfortunately, none of the residential or economic buildings survived, only the foundations are visible. The castle is currently managed by the agency of the Welsh cultural heritage (Cadw). It is open to visitors free of charge for most of the year.
Kenyon J., The medieval castles of Wales, Cardiff 2010.
Website wikipedia.org, White Castle, Monmouthshire.