William II DE BRAOSE, 10th Lord of Abergavenny
- Born: Before 5 Jan 1096, Abergavenny, Monmouthshire, Wales
- Married: Before 1140
- Died: After 1175, Weobley, Herefordshire, England
Orthographic variation: DE BRIOUZE.
Compiler's 23/25 x great-grandfather
The most difficult question relating to William [II] de Briouse is whether he in fact represents one person or two persons, father and son. If the charter dated to  is correctly dated, his life was improbably long if he was one person. In addition, the 1157 Pipe Roll lists William among "Nova Placita et Novæ Conventiones" for the honour of Barnstaple, which suggests that the William in question had recently inherited his property rights, presumably from his father as the death of his supposed grandfather Philippe is dated to [1131/39]. This looks straightforward until we consider the charter dated , which clarifies that Bertha of Gloucester was the wife of William, son of Philippe de Briouse, which appears to exclude their being two individuals named William.
"Philippus de Brausia" confirmed the donations to the church of Saints Gervais et Protais de Briouze, by "pater eius Guillemus de Brausia", before leaving for Jerusalem, by charter dated 5 Jan , with the consent of "uxor eius Aanor et Guillelmus filius suus". "Willielmus de Braiosa" confirmed the donations to the church of Saints Gervais et Protais de Briouze by "Philippus de Braiosa pater eiusdem Willielmi", by undated charter, witnessed by "Bertam conjugem meam, Philippum fratrem meum". "Willelmus de Braiosa, Philippi filius" notified "filio suo" that he had donated "Armigetone mansionem" to the monks of Saint-Florent by charter dated to , witnessed by "Robertus frater meus…", later confirmed by "Willelmus dominus de Braiosa filius Philippi, avi mei filii Willelmi" witnessed by "Bertam conjugem meam, Philippum fratrem meum…". A charter dated  records that "Willelmus de Braiosa et Willelmus de Harecourt" donated the church of Sumtinges to the Templars. This joint donation suggests a family relationship between the donors, but this has not yet been traced. The 1157 Pipe Roll records "Will’s de Braiosa" owing 1000 marks for "parte sua de honore de Barnestapl" in "Nova Placita et Novæ Conventiones". The 1157 Pipe Roll records "Will. de Braiosa" in Herefordshire. Military fee certifications in the Red Book of the Exchequer, in 1166, record the knights’ fees held from "Willelmi de Brahosa de honore de Berdestaple" in Devon. The Red Book of the Exchequer refers to "Willelmus de Breose xxviii m" in Devonshire in [1167/68]. The Red Book of the Exchequer records enfeoffments in the duchy of Normandy in , "Willemus de Braiosa" with three knights "de Braiosa".
He was Lord of Abergavenny and Brecon from  by grant of his brother-in-law Mahel FitzMiles.
The Annales Cambriæ record that "Willielmo de Breusa" killed "Seisil filius Dinawal et Gefrei filius eius…in Abergavenni" in 1175. “Willielmus de Braosa” confirmed donations to Abergavenny Priory by “Hamelinus de Balon et Brientius comitis filius et Walterus de Herefort et Henricus de Herefort” by undated charter, witnessed by “Rogero fratre meo…”. 1
William married Bertha DE GLOUCESTER, Heiress of Brecon, daughter of Miles Fitz Walter DE GLOUCESTER, Earl of Gloucester, and Cts Sybil DE NEUFMARCHÉ, before 1140. (Bertha DE GLOUCESTER was born in Brecon (Aberhonddu), Powys, Wales.)