Within the English revolution of the mid-seventeenth century which resulted in the triumph of the protestant ethic - the ideology of the propertied class - there threatened another, quite different, revolution. Its success 'might have established communal property, a far wider democracy in political and legal institutions, might have disestablished the state church and rejected the protestant ethic. In "The World Turned Upside Down" Christopher Hill studies the beliefs of such radical groups as the Diggers, the Ranters, the Levellers and others, and the social and emotional impulses that gave rise to them. The relations between rich and poor classes, the part played by wandering 'masterless' men, the outbursts of sexual freedom, the great imaginative creations of Milton and Bunyan - these and many other elements build up into a marvellously detailed and coherent portrait of this strange, sudden effusion of revolutionary beliefs.

Christopher Hill (1912-2003) was educated at St Peter's School, York, and at Balliol College, Oxford, and in 1934 was made a fellow of All Souls College, Oxford. In 1936 he became lecturer in modern history at University College, Cardiff, and two years later fellow and tutor in modern history at Balliol. After war service, which included two years in the Russian department of the Foreign Office, he returned to Oxford in 1945. From 1958 until 1965 he was university lecturer in sixteenth- and seventeenth-century history, and from 1965 to 1978 he was Master of Balliol College.

His publications include Lenin and the Russian Revolution; Puritanism and Revolution; God's Englishman: Oliver Cromwell and the English Revolution; The World Turned Upside Down; Milton and the English Revolution, which won the Royal Society of Literature Award; A Turbulent, Seditious and Factious People: John Bunyan and His Church, which won the 1989 W. H. Smith Literary Award and The English Bible and the Seventeenth-Century Revolution, which was shortlisted for the 1993 NCR Book Award.