Gwilym ap Tudur Rhys and Owain Glyndŵr. As a result, the Tudur brothers began planning an attack on Conway Castle. On Good Friday, 1 April 1401, the brothers and 44 men (which included those who had also been excluded from the pardons) infiltrated the castle. They had pretended to be carpenters, and captured the castle while the guard were in church. Negotiations began for the return of the castle on 13 April, with the king represented by Henry "Hotspur" Percy and Gwilym representing the Welsh forces. After seeking a compromise, which would have resulted in pardons being given to the Welshmen, the king
Battle of Bryn Glas weather. Early in 1402, Glyndwr's men ambushed and captured Grey of Ruthyn, who had indirectly caused the rebellion, and held him for ransom. In June, Glyndwr himself was near Knighton, and only from Leominster, then an important English garrison and market town in the Welsh Marches. King Henry had appointed Henry Percy, widely known as "Hotspur", as his principal lieutenant and justiciar in North Wales and the adjacent Marches. Hotspur's uncle, the Earl of Worcester, held a similar appointment in the south. However, the force which confronted Glyndwr near Knighton was a county levy of Herefordshire under Sir Edmund Mortimer.