By the 1840s Joseph Haydn, who died in 1809 as the most celebrated composer of his generation, had degenerated into the bewigged "Papa Haydn," a shallow placeholder in music history who merely invented the forms used by Beethoven. In a remarkable reversal, Haydn swiftly regained his former stature within the opening decades of the twentieth century. Reviving Haydn: New Appreciations in the Twentieth Century examines both the decline and the subsequent...