BattlefieldsBattle of Seisyll's Court
Medieval

Battle of Seisyll's Court

1175
Wales
Era
Medieval
Battle Type
Pitched Battle
Location
Wales
Status
Unregistered
The Combatants

Who Fought

Defeated
Seisyll ap Dyfnwal and the Welsh leaders
VS
Victor
William de Braose
Outcome
Welsh leaders, including Seisyll ap Dyfnwal, killed by William de Braose's men at Abergavenny Castle
The Battle

History & Significance

In 1175, William de Braose carried out what became known as the Abergavenny Massacre, inviting Welsh leaders to a Christmas feast at Abergavenny Castle under the pretence of peace and the settling of outstanding differences at the year's end, a tradition among the Welsh. His principal target was Seisyll ap Dyfnwal, of Castell Arnallt near Llanover in the valley of the River Usk near Abergavenny, whom de Braose held responsible for the death of his uncle Henry. Once the Welsh leaders were gathered, de Braose had them murdered by his men, an act that earned him the name the "Ogre of Abergavenny" among the Welsh and generated great hostility towards him.

The killing of Seisyll ap Dyfnwal did not end the violence. According to the source on Dingestow, Hywel ap Iorwerth, the Welsh lord of Caerleon, launched a retaliatory attack in 1182 on a Norman castle under construction at Dingestow by Ranulf Poer, Sheriff of Herefordshire. The sheriff was killed in the action. De Braose himself was said to have hunted down and killed Seisyll ap Dyfnwal's surviving son, Cadwaladr, a boy of seven, further inflaming Welsh sentiment against him.

Suspected site. The exact location is uncertain.
Buried history

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.

Casualties & Losses

Seisyll ap Dyfnwal and other Welsh leaders killed; later, Ranulf Poer, Sheriff of Herefordshire, killed in retaliatory Welsh attack at Dingestow (1182)

Forces Involved

not recorded

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Sources