He chose to set the traditional Latin Mass for the Dead interwoven with nine poems about war by the English poet Wilfred Owen.

Owen, who was born in 1893, was serving as the commander of a rifle company when he was killed in action on 4 November 1918 during the crossing of the Sambre–Oise Canal in France, just one week before the Armistice.

Philip Reed has discussed the progression of Britten's composition of the War Requiem in the Cambridge Music Handbook publication on the work.

[6] Britten dedicated the work to Roger Burney, Piers Dunkerley, David Gill, and Michael Halliday.

According to the Britten-Pears Foundation's War Requiem website, Dunkerley, one of Britten's closest friends, took part in the 1944 Normandy landings.

[7] The musical forces are divided into three groups that alternate and interact with each other throughout the piece, finally fully combining at the end of the last movement.

[9] The Requiem aeternam, Dies irae, and Libera me movements end in a brief choral phrase, consisting mainly of slow half notes, each first and second phrase ending on a tritone's discord, with every last (i. e. third) phrase resolving to an F-major chord; while at the end of the Agnus Dei the tenor (in his only transition from the Owen poems to the Requiem liturgy, on the key words, Dona nobis pacem – Give us peace) outlines a perfect fifth from C to G before moving down to F♯ to resolve the chorus's final chord.

At the end of the Dies irae, the tenor sings (from Owen's "Futility") "O what, what made fatuous sunbeams toil, to break earth's sleep at all?"

These motifs form a substantial part of the melodic material of the piece: the setting of "Bugles sang" is composed almost entirely of variations of them.

Although there are a few occasions in which members of one orchestra join the other, the full forces do not join until the latter part of the last movement, when the tenor and baritone sing the final line of Owen's poem "Strange Meeting" ("Let us sleep now ...") as "In Paradisum deducant" ("Into Paradise lead them ...") is sung first by the boys' choir, then by the full choir (in 8-part canon), and finally by the soprano.

For the opening performance, Britten intended that the soloists should be Galina Vishnevskaya (a Russian), Peter Pears (an Englishman) and Dietrich Fischer-Dieskau[11][12] (a German), to demonstrate a spirit of unity.

[14] Although the Coventry Cathedral Festival Committee had hoped Britten would be the sole conductor for the work's premiere, shoulder pain forced his withdrawal from the main conducting role.

[21] The North American premiere was at Tanglewood, with Erich Leinsdorf conducting the Boston Symphony Orchestra with soloists Phyllis Curtin, Nicholas Di Virgilio, Tom Krause and choruses from Chorus Pro Musica and the Columbus Boychoir, featuring boy soprano Thomas Friedman.

The English Chamber Choir performed the work at Your Country Needs You, an evening of "voices in opposition to war" organised by The Crass Collective in November 2002.

[28] The first recording, featuring Vishnevskaya, Fischer-Dieskau and Pears, with the London Symphony Orchestra and The Bach Choir conducted by Britten, was produced by Decca in 1963.

Within five months of its release it sold 200,000 copies, an unheard-of number for a piece of contemporary classical music at that time.