Owain Glyndŵr or Owen Glendower [ˈoʊain ɡlɨ̞nˈduːr], born c. 1349-1359 and d. 1412, was the Prince of Wales and Lord of Glyndyfrdwy and of Cynllaith Owain. In 1400, he proclaimed himself Prince of Powys, and subsequently revolted unsuccessfuly against the English. He is commonly referred as the father of Welsh nationalism.
Circa 1383, he married Margaret Hanmer, the daughter of his Law professor. After his disappearance and death in 1412, having never captured nor betrayed, his son Maredudd ab Owain Glyndŵr continued to rally opposition in North Wales with a force of Scots.
Fun fact: he came 23rd in BBC's 100 Greatest Britons 2002 poll and was the highest Welsh entry of the list.
Circa 1383, he married Margaret Hanmer, the daughter of his Law professor. After his disappearance and death in 1412, having never captured nor betrayed, his son Maredudd ab Owain Glyndŵr continued to rally opposition in North Wales with a force of Scots.
For more info about this figure, visit the Wikipedia article about him here.