Zulu is a 1964 epic war film depicting the Battle of Rorke's Drift between the British Army and the Zulus in January 1879, during the Anglo-Zulu War. It depicts 150 British soldiers, many of whom were sick and wounded patients in a field hospital, who successfully held off a force of 4,000 Zulu warriors.
The ending of the film is somewhat fictitious. There was no Zulu attack at dawn on 23 January 1879, which in the film led to the singing of "Men of Harlech", but it sure made for dramatic Hollywood an ending to be viewed again and again.
Men of Harlech is widely used as a regimental march, especially by British Army and Commonwealth regiments historically associated with Wales. Notably, it is the slow march of the Welsh Guards, and the quick march of the Royal Welsh.
It was first used for cinema during the titles of How Green Was My Valley (1941) and has featured in a number of other films. It is best known for its prominent role in the 1964 film Zulu, although the version of lyrics sung in it were written specially for the film. It is sung twice, only once completely, in the film (the British begin shooting the charging Zulus before the start of the final couplet), in counterpoint to the Zulu war chants and the sounds of their shields. Film editor John Jympson cut the scene to the song so that on either side of cuts where the British soldiers cannot be heard, the song is in the correct relative position. The song is also heard in the film Zulu Dawn, which is about the battle that precedes Rorke's Drift, the Battle of Isandlwana.