Religion has always been central to explanations of the political and ideological causes and course of the English civil war. Where historians once privileged aspects of the conflict that associated it with a broader narrative about the historic development of religious toleration and parliamentary democracy, the 1980s witnessed a shift whereby it was more firmly contained within local and European contexts. More recently, there has been an effort to place the civil war within another broad context, yet one that traces its roots in the Reformation rather than its legacies in the 18th and 19th centuries. However, a question remains as to what the English Reformation meant for the relationship of civil and ecclesiastical power: in many ways this was the key issue that shaped the politics of religion in the English civil war. This essay suggests that we understand the politics of religion more effectively by situating the conflict within the wider contexts opened up by Atlantic and imperial history.