While arguably central to the human experience, religion is a largely understudied component of social life and of politics. The comparative literature on religion and politics is limited in scope, and offers mostly descriptions of trends. We know, for example, that restrictions on freedom of religion are on the rise worldwide. In our theoretical framework, the recently higher universal levels of globalization combine with other sources of threat to account for the trend away from religious freedom. As threat to the majority religion increases, due to globalization and an increasing number of minority religions, freedom of religion is on the decline. Data for two decades from 147 nations are used to test hypotheses. Time-series cross-sectional and mediation models estimated at different levels of analysis with data from two independent sources confirm that threat systematically accounts for changes in religious freedom, with globalization playing a key role.