Pew Research Center measured relationships between religion and government in 199 countries and self-administering territories, using data for the year ending Dec. 31, 2015. They include the 193 member states of the United Nations as of 2015, plus six self-administering territories – Kosovo, Hong Kong, Macau, the Palestinian territories, Taiwan and Western Sahara.

The study analyzes country constitutions and basic laws as well as secondary sources from governmental and nongovernmental organizations to categorize relationships between religion and government in each country. Each country’s laws, as well as official policies and actions toward religious groups, were taken into account when classifying this relationship.

Research on this topic was conducted in tandem with the annual coding process for the Center’s study of global restrictions on religion, using the same 18 widely available, frequently cited sources of information on government restrictions and social hostilities involving religion around the world. A complete list of sources and details for our religious restrictions coding methodology is available here.

This research is part of a broader effort to understand restrictions on religion around the world. For the past eight years, Pew Research Center has published annual reports analyzing the extent to which governments and societies around the world impinge on religious beliefs and practices. The studies are part of the Pew-Templeton Global Religious Futures project, which analyzes religious change and its impact on societies around the world. The project is jointly funded by The Pew Charitable Trusts and the John Templeton Foundation.