"Men of Harlech" or "The March of the Men of Harlech" is a song and military march which is traditionally said to describe events during the seven-year siege of Harlech Castle between 1461 and 1468. Commanded by Constable Dafydd ap Ieuan, the garrison withstood the longest known siege in the history of the British Isles. The song has also been associated with the earlier, briefer siege of Harlech Castle about 1408, which pitted the forces of Owain Glyndŵr against the future Henry V of England.
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