castle and village, Gwynedd county, historic county of Merioneth (Meirionnydd), Wales, on the coast of Cardigan Bay. In 1283, after defeating Llywelyn ap Gruffudd, the English king Edward I began construction of a fortress there on the edge of a prominent cliff. This castle has had a long history of occupation and assault. In the early 15th century Owen Glendower captured it and held a parliament there. During the Wars of the Roses the English queen Margaret took refuge there in 1460, when Henry VI, her husband, had been captured, and Harlech Castle was the last Welsh fortress to surrender to the Yorkists in 1468 (its defense is commemorated in the battle song March of the Men of Harlech). In 1647 it was the last Welsh fortress that surrendered to the Parliamentary armies in the English Civil Wars.
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