From the 1560s, tensions between Protestant and Catholics escalated and this was accompanied by a wave of writing on political and religious ideas, especially in France and the Netherlands. There was a renewed interest in the nature and origins of authority within the political sphere, particularly the importance of the ‘people’ and the ways in which their will could be both represented and controlled. This chapter considers some of the key texts of resistance theory written in the 1560s and 1570s, including Francogallia and the Vindiciae, Contra Tyrannos in France, and George Buchanan’s De Jure Regni apud Scotos in Scotland. Discussions of liberty and privileges in the Netherlands during the Dutch Revolt are also considered; here historically based arguments began to be supplemented by appeals to wider principles of morality and natural law. The election of Henry of Valois to the Polish throne provides one example of elective monarchy in practice. This chapter discusses the role of religion and of legal arguments in the development of resistance theories. It also highlights some of the practical and conceptual difficulties in appealing to popular sovereignty, especially in a period of deep confessional divisions, and shows how the authority of magistrates could be understood in different ways.