Vaughan Williams was in his late sixties when an opportunity to write for the cinema materialised. He was approached by his former pupil Muir Mathieson, the director of music for the Ministry of Information, to write the score for the film 49th Parallel.
The plot for 49th Parallel is set in the early part of World War II, when a German U-Boat sinks allied shipping in the Gulf of St. Lawrence and then tries to evade capture by the Canadian Military by sailing up to Hudson Bay. A handful of crew disembark to look for supplies and no sooner have they reached shore when the U-Boat is spotted by the Canadian Armed Forces and sunk. Leaving the shore party stranded in Canada they have no other option but to head for the neutral United States and, as their ill-fated journey unfolds, they meet a variety of characters whom they alienate due to their reprehensible actions. They These include a pacifist in the Canadian wilds played by Leslie Howard, a Hutterite leader, and a French-Canadian fur trapper, played by Laurence Olivier. The film premièred in the UK in October 1941 and in March 1942 for the US, when it was retitled The Invaders.
The brass band suite to 49th Parallel, devised by Paul Hindmarsh and arranged by Phillip Littlemore, takes the Prologue from the cinematic score as its starting point. Stretches of pastoral musical themes depict the Canadian landscape before the atmosphere is broken with a menacing rendition, albeit briefly, of the Lutheran chorale Ein Feste Burg depicting the surfacing of the German U-Boat in the Gulf of St. Lawrence. This gives way to the mechanical, jaunty section Control Room Alert with its persistent drive and energy. A brief interlude of The Lake in the Mountains leads into the most recognised piece of music of from the film, the Prelude, which accompanied both the opening and closing credits, and adds a most fitting conclusion to this suite.
The suite has been recorded by the Tredegar Town Band, under their musical director Ian Porthouse, on the Albion Records CD Vaugham Williams on Brass.