More than 80 countries favour a specific religion, either as an official, government-endorsed religion or by affording one religion preferential treatment over other faiths. Islam is the most common government-endorsed faith, with 27 countries (including most in the Middle East-North Africa region) officially enshrining Islam as their state religion. By comparison, just 13 countries (including nine European nations) designate Christianity or a particular Christian denomination as their state religion. But an additional 40 governments around the globe unofficially favour a particular religion, and in most cases the preferred faith is a branch of Christianity. Indeed, Christian churches receive preferential treatment in more countries – 28 – than any other unofficial but favoured faith.

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