This collection arose as a result of a British Academy-sponsored conference, ‘The people all changed: religion and society in Britain during the 1650s’, held at the University of Portsmouth on 15–16 July 2016. The aim of the conference had been to shine a spotlight on this somewhat understudied period of British history, as well as to broaden the research perspective on the period beyond the political. Many of the contributions here began as papers at this conference. Thanks are due to the British Academy for a research grant facilitating both my own research and the organization of this conference. Thanks are also due to the University of Portsmouth for further funding the costs of the conference, and of my own research over the last few years. I am especially grateful to Professor Bernard Capp, for agreeing to write the introduction to this volume, and for his very hands-on involvement throughout the process of editing the different contributions. I had been told beforehand that Bernard was a ‘gent’ and so it has proved. His willingness to provide detailed constructive assistance to the many early career researchers in this collection has been very much appreciated. Warm thanks also to Dr Andrew Foster, for editorial assistance throughout the process, and to all the members of his early modern studies group meeting at Chichester, for many opportunities to chew the cud over mid-seventeenth-century religion.