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John of Monmouth

1182 – 1248

Anglo-Norman feudal lord born in Wales

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About John of Monmouth

Lived 1182 – 1248 (aged 65–66). John of Monmouth was a Welsh military personnel.

John of Monmouth (c. 1182 – 1248) was an Anglo-Norman feudal lord of Breton ancestry, who was lord of Monmouth between 1190 and 1248. He was a favourite of both King John and his son, Henry III, and one of the most powerful royal allies in the Welsh Marches.

Life He was born in Monmouth, the son of Gilbert fitzBaderon, and the great-grandson of William fitzBaderon who had been lord of Monmouth at the time of the Domesday Book in 1086. John's father died in about 1189, and, being under age, he was made the ward of his uncle, William de Braose, 4th Lord of Bramber, Sheriff of Herefordshire and a court favourite. He was still a ward of de Braose at the time of King John's accession to the throne of England in 1199, but, by 1201, he had married Cecilia de Waleran and paid the king 120 marks and two Norway hawks for his share of her father's property.

He was appointed as Constable of St Briavels, and as a Justice in Eyre with responsibility for the law in royal forests. He became one of the most powerful figures in the southern Marches, serving as an advisor to the king on Anglo-Welsh affairs. In 1226, he established the Abbey of Grace Dieu, a few miles outside Monmouth, but the abbey faced constant attacks from the Welsh who claimed that John had seized Welsh land unlawfully; it was forced to relocate several times. John was also one of King Henry's allies in fighting the rebellions by the Welsh prince Llywelyn ab Iorwerth and Richard Marshal, Earl of Pembroke. However, he reportedly fled the Battle of Monmouth in 1233, when Richard Marshal's forces defeated the defenders of the town led by Baldwin III, Count of Guînes, and thereafter devastated the surrounding countryside. John returned to Monmouth afterwards, and over the next few years increased the extent of his control. He was made chief bailiff of South Wales in 1242, and at one point had control of Chepstow, Usk, Caerleon, Carmarthen, Builth and Cardigan as well as Monmouth. His second marriage, in about 1223/24, was to Agnes, the daughter of Walter de Muscegros. They had three sons: John, who became lord of Monmouth upon his father's death, Walter and Richard.

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Important facts

Born
1182, Monmouth
Birth century
Died
1248, Monmouth
Occupation
Nationality
Also known as
John de Monemue, John de Monmouth

People in John of Monmouth's life

Named in this biography and alive at the same time

Contemporaries

People whose lives overlapped John of Monmouth's

Frequently asked questions

Who was John of Monmouth?

Anglo-Norman feudal lord born in Wales

When was John of Monmouth born?

John of Monmouth was born in 1182 in Monmouth.

When did John of Monmouth die?

John of Monmouth died in 1248 in Monmouth.

What was John of Monmouth's occupation?

John of Monmouth was a military personnel.

What nationality was John of Monmouth?

John of Monmouth was Welsh.

Sources & further reading

· Wikipedia: John of Monmouth

· Wikidata: Q6265805

· DBpedia: John of Monmouth

Cite this page

APA: Biography.guide. (2026). John of Monmouth. https://biography.guide/john-of-monmouth-military-personnel/

MLA: "John of Monmouth." Biography.guide, https://biography.guide/john-of-monmouth-military-personnel/.

Chicago: "John of Monmouth." Biography.guide. https://biography.guide/john-of-monmouth-military-personnel/.

Data last updated: 2026-09-22 · Spot an error? Report a correction.

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