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Seisyll ap Dyfnwal
Encyclopedia
Seisyll ap Dyfnwal was a 12th century Welsh
Lord of Gwent Uwchcoed (Upper Gwent).
. He was a brother-in-law of Rhys ap Gruffydd
, the Lord Rhys, King of Deheubarth.
He held lands in present day Monmouthshire
, part of the old Welsh Kingdom of Gwent and his main base was at Castell Arnallt
, a motte and bailey style fortified site situated near the River Usk
a few miles south of Abergavenny
, near modern day Llanover
. It is today just a mound in a riverside field.
Baron
, William de Braose, 4th Lord of Bramber
, who had him murdered in cold blood on or very near Christmas Day 1175 at Abergavenny Castle
.
Seisyll was invited to Abergavenny Castle at Christmas along with all the other Welsh princes and leaders from the area by William De Braose on the understanding that they could voice grievances, overcome differences and plan a period of relative peace following a period of conflict. Some Welsh leaders stayed away, distrusting de Braose. Seisyll attended along with his eldest son Geoffrey. Most other leaders followed suit and attended, were assured of peaceful intent at the castle and surrendered their arms. Once inside the walls they were cut down by armed men without mercy.
De Braose and his men then mounted horses and galloped the few miles to Seisill's home where they caught and murdered his younger son, Cadwalladr a boy of seven years of age and captured his wife, whose exact fate is uncertain.
De Braose's strategy was to revenge his own uncle's death. His uncle Henry FitzMiles
, has been a victim of the Welsh earlier in the year. His exact killer was probably unknown but Seisill was apparently suspected. De Broase's strategy was to eliminate all those who could have done it and effectively remove the experienced leadership of the Welsh forces in the area, destabilising the region and seize the opportunity to gain the upper hand.
The effect was to drive a massive wedge between Anglo Welsh relations for generations to come.
Welsh people
The Welsh people are an ethnic group and nation associated with Wales and the Welsh language.John Davies argues that the origin of the "Welsh nation" can be traced to the late 4th and early 5th centuries, following the Roman departure from Britain, although Brythonic Celtic languages seem to have...
Lord of Gwent Uwchcoed (Upper Gwent).
Family and estates
Seisyll was the son of Dyfnwal ap Caradog ap Ynyr Fychan and his wife, said to have been Joyce daughter of Hamelin de BalunHamelin de Balun
Hamelin de Ballon was an early Norman Baron and the first Baron Abergavenny and Lord of Over Gwent and Abergavenny, titles granted shortly after the Norman Conquest of England and Wales by William the Conqueror; he also served William Rufus.- Origin :He was from France, from the ancient manor of...
. He was a brother-in-law of Rhys ap Gruffydd
Rhys ap Gruffydd
Rhys ap Gruffydd or ap Gruffudd was the ruler of the kingdom of Deheubarth in south Wales. He is commonly known as The Lord Rhys, in Welsh Yr Arglwydd Rhys, but this title may not have been used in his lifetime...
, the Lord Rhys, King of Deheubarth.
He held lands in present day Monmouthshire
Monmouthshire
Monmouthshire is a county in south east Wales. The name derives from the historic county of Monmouthshire which covered a much larger area. The largest town is Abergavenny. There are many castles in Monmouthshire .-Historic county:...
, part of the old Welsh Kingdom of Gwent and his main base was at Castell Arnallt
Castell Arnallt
Castell Arnallt , located below Abergavenny and near modern-day Llanover in the Usk Valley of Monmouthshire, Wales, was a fortification believed to have been the site of the palace of the Kings of Over Gwent...
, a motte and bailey style fortified site situated near the River Usk
River Usk
The River Usk rises on the northern slopes of the Black Mountain of mid-Wales, in the easternmost part of the Brecon Beacons National Park. Initially it flows north into Usk Reservoir, then east by Sennybridge to Brecon before turning southeast to flow by Talybont-on-Usk, Crickhowell and...
a few miles south of Abergavenny
Abergavenny
Abergavenny , meaning Mouth of the River Gavenny, is a market town in Monmouthshire, Wales. It is located 15 miles west of Monmouth on the A40 and A465 roads, 6 miles from the English border. Originally the site of a Roman fort, Gobannium, it became a medieval walled town within the Welsh Marches...
, near modern day Llanover
Llanover
- Location :Llanover is located four miles south of Abergavenny just off the A4042 road to Pontypool.- History & Amenities :Llanover is associated with Lady Llanover who lived locally all her life and certainly left her mark on the village and the surrounding Llanover estate, still privately owned...
. It is today just a mound in a riverside field.
Christmas massacre
Seisyll ap Dyfnwal is best known for being an unwitting victim of the NormanAnglo-Norman
The Anglo-Normans were mainly the descendants of the Normans who ruled England following the Norman conquest by William the Conqueror in 1066. A small number of Normans were already settled in England prior to the conquest...
Baron
Baron
Baron is a title of nobility. The word baron comes from Old French baron, itself from Old High German and Latin baro meaning " man, warrior"; it merged with cognate Old English beorn meaning "nobleman"...
, William de Braose, 4th Lord of Bramber
William de Braose, 4th Lord of Bramber
William de Braose, , 4th Lord of Bramber , 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.-Lineage:William was the most...
, who had him murdered in cold blood on or very near Christmas Day 1175 at Abergavenny Castle
Abergavenny Castle
Abergavenny Castle is a castle in the market town of Abergavenny, Monmouthshire in south east Wales.- A naturally fortified site :The castle was sited above the River Usk overlooking the river valley and the confluence of the rivers Gavenny and Usk. The site would have been naturally defensible in...
.
Seisyll was invited to Abergavenny Castle at Christmas along with all the other Welsh princes and leaders from the area by William De Braose on the understanding that they could voice grievances, overcome differences and plan a period of relative peace following a period of conflict. Some Welsh leaders stayed away, distrusting de Braose. Seisyll attended along with his eldest son Geoffrey. Most other leaders followed suit and attended, were assured of peaceful intent at the castle and surrendered their arms. Once inside the walls they were cut down by armed men without mercy.
De Braose and his men then mounted horses and galloped the few miles to Seisill's home where they caught and murdered his younger son, Cadwalladr a boy of seven years of age and captured his wife, whose exact fate is uncertain.
De Braose's strategy was to revenge his own uncle's death. His uncle Henry FitzMiles
Henry FitzMiles
Henry FitzMiles , Baron Abergavenny was a Norman baron and a Marcher Lord in the Welsh Marches.- Birth :...
, has been a victim of the Welsh earlier in the year. His exact killer was probably unknown but Seisill was apparently suspected. De Broase's strategy was to eliminate all those who could have done it and effectively remove the experienced leadership of the Welsh forces in the area, destabilising the region and seize the opportunity to gain the upper hand.
The effect was to drive a massive wedge between Anglo Welsh relations for generations to come.