Battle of Bryn Glas
The Battle of Bryn Glas (sometimes referred to in English accounts as the Battle of Pilleth) was fought on June 22, 1402, near Presteigne in Herefordshire (now also known as Llanandras, and in the Welsh county of Powys). It was a great victory for the Welsh rebels under Owain Glyndŵr, and it resulted in the prolongation of Glyndŵr's revolt and the destabilisation of English politics for several years afterwards.
Owain Glyndŵr's revolt had begun in 1400 as a private war with an English neighbour, and had rapidly grown into a national insurrection. In the classic pattern of insurgencies, his forces had progressed from hit-and-run attacks to seeking confrontation with major enemy forces.
King Henry IV had appointed Sir Edmund Mortimer as his principal lieutenant in the Marches. Mortimer was uncle of the Earl of March who had a better claim in theory to be King of England, but Edmund had so far loyally supported Henry. In any case, as a substantial holder of lands in Wales and on the borders, Mortimer had already suffered from the depredations of Glyndŵr's rebels and had much to lose should the revolt continue.
Mortimer's army, which numbered about 8000, was seeking to bring Glyndŵr's smaller army to battle. Although the location was only just inside Wales, Glyndŵr undoubtedly had many local informants and sympathisers, and could plan a decisive battle. Probably, he had also been able to summon reinforcements from other parts of Wales, which moved rapidly over hill tracks, and was therefore far stronger than Mortimer realised.
Part of Glyndŵr's army, numbering perhaps 3000, occupied a hillside above the valley along which Mortimer's army was advancing. Mortimer's army formed up and attacked directly up the steep slope. They suffered severely from Glyndŵr's archers, who had the advantage of height, before being able to fight hand-to-hand. When they were fully engaged, they were attacked in the flank and rear by the other half of Glyndŵr's army which had been concealed in woods on the English right flank. Further disruption and panic were caused when Welsh contingents in Mortimer's army defected, and attacked their former comrades.
It is said that immediately after the battle, many English corpses were mutilated by Welsh women camp followers, in revenge for a punitive expedition by Henry IV the previous year which had been marked by many acts of brutality and rape.
Mortimer was captured, and subsequently renounced his allegiance to Henry, put forward his nephew's claim to the throne of England and married Glyndŵr's daughter Caitrin.
A computer-animated reconstruction of the battle was featured in the BBC series, "Battlefield Britain", narrated by Jon Snow.