Battle of Seisyll's Court
Who Fought
History & Significance
William de Braose, (or William de Briouze), 4th Lord of Bramber (1144/1153 – 9 August 1211), court favourite of King John of England, at the peak of his power was also Lord of Gower, Abergavenny, Brecknock, Builth, Radnor, Kington, Limerick, Glamorgan, Skenfrith, Briouze in Normandy, Grosmont, and White Castle.
William was the most notable member of the de Braose dynasty. His steady rise and sudden fall at the hands of King John is often taken as an example of that king's arbitrary and capricious behaviour towards his barons.
William was the son of William de Braose, 3rd Lord of Bramber and his wife Bertha of Hereford, also known as Bertha de Pitres (born c. 1130), daughter of Miles Fitz Walter, Earl of Hereford and his wife, Sibyl, daughter of Bernard de Neufmarché. From his father, he inherited the Rape of Bramber, in Sussex, and through his mother, he inherited a large estate in the Welsh Marches area of modern-day Monmouthshire.
In 1175, William de Braose carried out the Abergavenny Massacre, luring three Welsh princes and other Welsh leaders to their deaths. His principal antagonist was a Seisyll ap Dyfnwal, of Castell Arnallt near Llanover in the valley of the River Usk near Abergavenny, whom he blamed for the death of his uncle Henry.
After having invited the Welsh leaders to a Christmas feast at Abergavenny Castle under the pretence of peace and the start of a new era at the end of the year (a traditional time for settling outstanding differences amongst the Welsh), he had them murdered by his men. This resulted in great hostility against him among the Welsh, who named him the "Ogre of Abergavenny".
Gerald of Wales exonerates him and emphasises the religious piety of de Braose and his wife and de Braose generosity to the priories of Abergavenny and Brecon. William de Braose did however reputedly hunt down and kill Seisyll ap Dyfnwal's surviving son, Cadwaladr, a boy of seven.
In 1192, William de Braose was made sheriff of Herefordshire, a post he held until 1199. In 1196 he was made Justice Itinerant for Staffordshire. In 1195 he accompanied King Richard I of England to Normandy and in 1199, William de Braose fought beside Richard at Châlus, where the king was mortally wounded. He then supported King John's claim to the throne of England, and represented the new king, making various royal grants.
In 1203, William de Braose was put in charge of Arthur of Brittany, whom he had personally captured the previous year at the Battle of Mirebeau. William was suspected of involvement in Arthur's disappearance and death, although no concrete evidence ever came to light. There is somewhat better evidence that he at least knew the truth of the matter. William was in attendance with John in Normandy at the time of Arthur of Brittany's imprisonment and it was alleged that Arthur suffered the same fate as the Welsh princes at William's hand, although this has never been proven. Arthur's death remains a mystery. After Arthur disappeared, De Braose served in the war of 1204 against King Philip II of France in France.
The ground they fought on
The site of Battle of Seisyll's Court lies on Pridoli Rocks (Undifferentiated), bedrock that formed in the Pridoli. The rock here is mudstone, siltstone and sandstone.
The murders at Abergavenny Castle on Christmas Day 1175 were carried out under the cover of a seasonal feast, a time traditionally associated among the Welsh with the settling of differences; de Braose exploited this custom to lure Seisyll ap Dyfnwal and other Welsh leaders to their deaths, an act of treachery that provoked years of Welsh retaliation, including the killing of the Sheriff of Herefordshire at Dingestow in 1182.
- Seisyll ap Dyfnwal and other Welsh leaders killed; later, Ranulf Poer, Sheriff of Herefordshire, killed in retaliatory Welsh attack at Dingestow (1182)
Frequently Asked Questions
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- William de Braose, 4th Lord of Bramber · Wikipedia
- Dingestow · Wikipedia