The crisis of theory tells the story of the political and intellectual adventures of E. P. Thompson, one of Britain's foremost twentieth-century thinkers. Drawing on extraordinary new unpublished documents, Scott Hamilton shows that all of Thompson's work, from his acclaimed histories to his voluminous political writings to his little-noticed poetry, was inspired by the same passionate and idiosyncratic vision of the world. In a narrative that moves from the battlefields of Spain and Italy to the coal towns of Yorkshire to the bloody chaos of Emergency India, Hamilton presents Thompson as a man determined to find an alternative, in thought and in action, to the ideologies of Stalinism and right-wing 'Natopolitanism' that together dominated the postwar world. Hamilton shows the connection between Thompson's famously ferocious attack on the 'Stalinism in theory' of Louis Althusser and his assaults on positivist social science in books like The making of the English working class, and he produces previously unseen evidence to show that Thompson's hostility to both left and right-wing forms of authoritarianism was rooted in first-hand experience of violent political repression. Although Thompson's thought was a response to the great events of the twentieth century, Hamilton argues that it is more relevant than ever in the age of the War on Terror, extraordinary rendition, and capitalist globalisation. This book will appeal to scholars and general readers with an interest in left-wing politics and theory, British society, twentieth-century history, modernist poetry, and the philosophy of history.