Ella Fitzgerald (1917-1996) possessed one of the twentieth century's most astonishing voices. In this first major biography since Fitzgerald's death, music historian Judith Tick draws on deep archival research, family interviews and newly available recordings and concert footage to show how Fitzgerald fused a Black vocal aesthetic with mainstream popular repertoire to revolutionise American music. From Fitzgerald's first audition at the Apollo Theatre to swing-era success at the Savoy, Tick shows how this "girl singer" broke new ground: as a female bandleader, as a ground-breaking bebop improviser and as the arbiter of the American canon with her Song Book recordings. Yet even as she electrified concert halls and sold millions of records, jazz critics belittled her as "naive". Tick reveals instead an ambitious risk-taker with a stunningly diverse repertoire, whose exceptional musical spontaneity (often radically different on stage than in the studio) made her a transformational artist.