Background
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.
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.
Like William de Braose, he had a close relationship with the king, who visited Monmouth in 1213 on a hunting expedition. When the king died in 1216, John of Monmouth was present at his bedside, and was one of the executors of his will. He was also involved in the coronation of John"s son and successor, Henry III. He was appointed as Constable of Street 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. lieutenant was forced to relocate several times.
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.
He died in 1247 or 1248, and was buried at Monmouth. His tomb was destroyed in the rebuilding of the Priory Church of Street Mary in 1737. He died in 1274.
