Although Friedrich Engels was Marx's intellectual partner, he has been one of the most neglected of the major socialist thinkers. This major book aims neither to defend Engles or debunk him, but rather to engage with his thought in order to offer a critical assessment of the philosophy, social theory, and politics of Marxism. S.H. Rigby shows how many of the key issues of Marxist thought, such as Marxism's debt to Hegelianism, the nature of historical materialism and the relationship between class and gender, were most explicitly dealt with Engels, rather than by Marx himself. He examines Engels' contribution to the genesis of Marxism in the years before 1848, and examines the extent to which Engles' later writings departed for his and Marx's outlook of the 1840's, He asks whether Marx shared Engels' intellectual development, questions recent attempts to divorce the views of Marx from those of Engels, and criticizes those Marxists who have used Engels as a scapegoat in order to avoid a confrontation with problems that lie at the very heart of Marxism.