Walter Devereux (1411–1459)
Following the death of Edmund Mortimer, 5th Earl of March, on 18 January 1425, Richard, 3rd Duke of York inherited his estates along the Welsh Marches. This brought Walter Devereux into the retinue of the Duke, and he remained his loyal supporter throughout the War of the Roses. Devereux had been knighted by 22 September 1429 when he first represented Herefordshire in Parliament. He probably was in attendance on the Duke when he travelled with Henry VI to France for his coronation on 16 December 1429. On his return Devereux represented Herefordshire again in Parliament on 16 January 1430. He was listed on the subsidy rolls for Herefordshire of 12 January 1431 as holding his 1/3 of half a fee in Byford.
William Devereux, Baron Devereux of Lyonshall
It was this ongoing warfare that led to a resumption of the Welsh Wars when Llywelin was declared a rebel on 12 November 1276. William Devereux was summoned for military service 12 December 1276 to May 1279 against the Welsh. It is probable that he was with Bohun as the earl initially suppressed the rebellion in Brecon, and then joined the main army for its advance into Wales in February 1277. On 2 July 1277 Devereux was summoned to muster at Worcester for military service against Llywelyn, Prince of Wales, and participated in the seizure of the harvest on Anglesey that summer. Following the Treaty of Aberconwy on 9 November 1277 hostilities lessened, but ongoing disturbances continued over the next few years as Edward I tried to extend English law and systems into Wales.