From 1404 to 1413 he served with his elder brother Gilbert in the Welsh revolt or the rebellion of Owain Glyndŵr. Meanwhile, he was summoned to Parliament in his wife's right from 1409. Then for five years from February 1414 he was Lord Lieutenant of Ireland, where he did some fighting. He had a dispute with James Butler, 4th Earl of Ormond and Reginald Grey, 3rd Baron Grey de Ruthyn over the inheritance for the honour of Wexford which he held. Complaints were made against him both for his harsh government in Ireland and for acts of violence in Herefordshire, where he was a friend of the Lollard Sir John Oldcastle, and for land disputes with retainers of the Earl of Arundel.