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
Owain Glyndŵr were leaving their studies to join Owain, and Welsh labourers and craftsmen were abandoning their employers in England and returning to Wales. Owain could also draw on Welsh troops seasoned by the English campaigns in France and Scotland. Hundreds of Welsh archers and experienced men-at-arms left English service to join the rebellion. In 1404, Owain held court at Harlech and appointed Gruffydd Young as his Chancellor. Soon afterwards, he called his first Parliament (or or "gathering") of all Wales at Machynlleth, where he was crowned Prince of Wales and announced his national programme. He declared his vision of an independent