He had been squire of the body to Richard the Second, and had clung to him till he was seized at Flint.

It was probably his known aversion from the revolution which had deposed his master that brought on him the hostility of Lord Grey of Ruthin, the stay of the Lancastrian cause in North Wales; and the same political ground may have existed for the refusal of the Parliament to listen to his prayer for redress and for the restoration of the lands which Grey had seized.

But the refusal was embittered by words of insult; when the Bishop of St.
Asaph warned them of Owen's power the lords retorted that "they cared not for barefoot knaves." They were soon to be made to care.

At the close of 1400 Owen rose in revolt, burned the town of Ruthin, and took the title of Prince of Wales.
[Sidenote: Owen Glyndwr] His action at once changed the disaffection into a national revolt.

His raids on the Marches and his capture of Radnor marked its importance, and Henry marched against him in the summer of 1401.