Winner of the Pierlot Prize in Contemporary History, this political biography of Emile Vandervelde traces the European socialist path at the turn of the century as it wended its way from Marx's writings to the practices of social democrats in the interwar period. Vandervelde defined democratic socialism as a compromise between orthodox and revisionist Marxism.

As President of the Second International, he brought French, British, and German socialists together as comrades in a common revolutionary struggle.