“Men of Harlech” or “The March of the Men of Harlech” (Welsh: Rhyfelgyrch Gwŷr Harlech) is a song and militarymarch which is traditionally said to describe events during the seven-year siege of Harlech Castle between 1461 and 1468, when the castle was held by the Lancastrians against the Yorkists as part of the Wars of the Roses. Commanded by Constable Dafydd ap Ieuan, the garrison withstood the longest known siege in the history of the British Isles. (“Through Seven Years” is an alternative name for the song.) 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.
“Men of Harlech” is important for Welsh national culture. The song gained international recognition when it was featured in the 1941 movie How Green Was My Valley and the 1964 film Zulu.