Roger Mortimer (1231-1282), 1st Baron Wigmore , was the son of Ralph de Mortimer and his wife, Gwladys Ddu -- daughter of Llywelyn the Great. He was a famous and honored knight, and a loyal ally of King Henry III of England. He was at times an enemy, at times an ally, of Llywelyn the Last.

Mortimer fought for the king against the rebel Simon de Montfort, 6th Earl of Leicester, and almost lost his life in 1264 at the Battle of Lewes fighting Montfort's men. In 1265 Mortimer helped rescue Prince Edward and they made common cause to lure Montfort into a trap.

In August 1265, Montfort's army was surrounded by the River Avon on three sides, and Prince Edward's army on the fourth. Mortimer had sent his men to block the only possible escape route, at the Bengeworth bridge. The Battle of Evesham began in earnest. A storm roared above the battle field. Montfort's Welsh soldiers broke and ran for the bridge, where they were slaughtered by Mortimer's men. Mortimer himself killed Hugh le Despencer, 1st Baron le Despencer. Finally, the royalist forces crushed Montfort's army and killed Simon de Montfort himself. Mortimer was awarded Montfort's severed head, which he sent home to Wigmore castle as a gift for his wife, Lady Mortimer.

Lady Mortimer was Maud de Braose, daughter of William de Braose, Lord of Abergavenny by Eva Marshall. Roger Mortimer had married her in 1247. She was, like him, a scion of a Marcher family. Their children were:

1. Ralph Mortimer, died 1276.
2. Edmund Mortimer, 2nd Baron Wigmore (1251-1304)
3. Isabella Mortimer, died 1292. She married (1) John Fitzalan, 7th Earl of Arundel, (2) Robert de Hastings
4. Margaret Mortimer, died 1297. She married Robert de Vere, 6th Earl of Oxford
5. Roger Mortimer of Chirk , died 1326.
6. Geoffrey Mortimer, a knight
7. William Mortimer, a knight

Their eldest son, Ralph, was a famed knight but died in youth. The second son, Edmund, was recalled from Oxford University and made heir. Roger Mortimer died in 1282, and was buried at Wigmore Abbey, where his tombstone reads:

"Here lies buried, glittering with praise, Roger the pure, Roger Mortimer the second, called Lord of Wigmore by those who held him dear. While he lived all Wales feared his power, and given as a gift to him all Wales remained his. It knew his campaigns, he subjected it to torment."

Sources

• Mortimer, Ian. The Greatest Traitor, 2003.
• Dugdale, Sir William. The Baronage of England, Vol. 1, 1661.