Abstract: This study examines how British musical modernism articulated new versions of history and community in the wake of the Second World War, within a project of social reconstruction and cultural renewal that occupied artists, public intellectuals, and social planners. Music in particular became enmeshed in the machinery of cultural planning through powerful new institutions for its funding, broadcasting, and performance. While this study treats a broad spectrum of musical culture, its central focus is a set of works by Benjamin Britten that grapple with what an art music for postwar Britain should be. My narrative follows a trajectory from the composer's return to England in 1942, through the height of his participation in British cultural life and his most public musical deeds in the late forties and fifties, closing with the War Requiem of 1962. With A Ceremony of Carols (1942), I explore how the medieval carol was used to find a space between elite and popular culture. The opera Gloriana (written for the Coronation of Elizabeth II) provides a window onto the Coronation's governing trope of “New Elizabethanism,” articulating it in ways that brought a competing version of Englishness to the event. I discuss how Noye's Fludde (1958) ritually enacts communal renewal through the reincorporation of scattered remnants of an English Christian tradition, interacting closely with the medieval Mystery productions of the York Festival (instituted as part of the Festival of Britain in 1951) while also using the ideas of hearing and singing to construct a specifically musical relationship with the past. The dissertation concludes with a monument of postwar reconstruction, the War Requiem (1962), examining its relationship with the rebuilding of Coventry Cathedral which it was commissioned to mark. These works embody distinguishable discourses about the relationship of past and present, elite and popular culture, and the ways art can create community in an increasingly secular, diverse, and egalitarian Britain. Their ambivalence, I argue, testifies to more than Britten's own sense of marginality as a gay, left-leaning pacifist in the cultural Establishment. Rather, these works probe areas of uncertainty at the very heart of postwar ideals of culture and community.