Reginald Grey, 3rd Baron Grey de Ruthyn
Glyndŵr tried to take legal action in 1400, but the court told him to give the land to Grey. Grey also did not tell Glyndŵr that his men were needed service in Scotland until the last moment. This made it impossible for Glyndŵr to send the men or even send an explanation for not sending them. Refusing or failing to follow an order of the King was treason. Glyndŵr's lands were would be taken until he could prove he was loyal to the king or receive punishment. On 16 September Glyndŵr and his brothers burned Grey's property. For three days his Welsh forces attacked the countryside of Flintshire and Denbighshire. On 24 September, Glyndwr's forces were defeated at Welshpool.