Glyndŵr

Owain ap Gruffydd of Glyndyfrdwy and Sycharth (c.1359–c.1415) descended from the princely lines of both Powys Fadog and Deheubarth. He was educated at the Inns of Court in London, served the English crown in arms in Scotland and Flanders in the 1380s, and lived as a Welsh gentleman of substantial standing at his hall at Sycharth in northern Powys until 1400.

The dispute that triggered the revolt was a boundary quarrel with his English-baron neighbour Reginald Grey of Ruthin, mishandled by Henry IV's parliament in 1399. On 16 September 1400 Glyndŵr was proclaimed Prince of Wales by his own retinue at Glyndyfrdwy. Within five years his authority extended over almost the whole of Wales. He held parliaments at Machynlleth in 1404 and Harlech in 1405. He proposed an independent Welsh church under Rome, two Welsh universities, and an alliance with Charles VI of France — sealed by treaty in 1404 and reinforced by a French expeditionary force that landed at Milford Haven in 1405.

By 1409 Henry IV's son — the future Henry V — had broken the field force. Aberystwyth fell, Harlech fell, the prince's family was taken to the Tower of London. Glyndŵr himself was never captured. The last sighting was in 1412. Where and when he died, no English chronicle records and no Welsh source claims to know — by tradition under his own name in the borderlands of Herefordshire, around 1415. The revolt was the last attempt to restore an independent Welsh principality, and the longest sustained native rising against the English crown anywhere in the British Isles.