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
Clun Castle of 1400–15, with Thomas playing a key role in suppressing the revolt; the castle was refortified and saw some service against the Welsh rebels led by Owain Glyndŵr. By the 16th century, the antiquarian John Leland observed the increasingly ruined nature of Clun Castle. Philip Howard, the 20th earl of Arundel, died in 1595 whilst under attainment, and James I gave Clun Castle to Henry Howard, 1st Earl of Northampton. The castle was abandoned by the time of the English Civil War of 1642–46 and saw no military action; it was slighted by Parliament, however, in 1646 to prevent any