This important new biography uses newly discovered material and takes a critical approach. Engels's formative years, before he met Marx, were crucial to the development of his thought. Carver is the first to analyse this early material in detail, revealing a surprising continuity in ambition and opinion over Engels's long career. Engels's personal and family relationships occupy centre-stage in this biography, and Engels the man emerges from Marx's shadow as a complex and engaging figure in his own right.