The Glyndŵr rebellion was a Welsh rebellion led between 1400 and c. 1415 by Owain Glyndŵr against the Kingdom of England during the Late Middle Ages. During the rebellion's height, Owain exercised control over the majority of Wales after capturing several of the most powerful English castles in the country, and formed a parliament at Machynlleth. The revolt was the last major manifestation of Welsh independence before the annexation of Wales into England in 1542–43.
The uprising began in 1400, when Owain Glyndŵr, a descendant of several Welsh royal dynasties, claimed the title Prince of Wales following a dispute with a neighbouring English lord.