The Geography of World Religions

Christianity, with roughly 2.3 to 2.4 billion adherents, is the world's largest religion by number of followers and is divided into three major branches with distinct regional strongholds. Roman Catholicism predominates in Latin America, Southern Europe, and the Philippines; Protestantism is historically concentrated in Northern Europe and North America, while also growing rapidly in Sub-Saharan Africa and South Korea; and Eastern Orthodoxy predominates in Russia, Greece, the Balkans, and Ethiopia. Islam, with close to 1.9 billion adherents, is the second-largest religion and is itself divided into Sunni and Shia branches, though its geographic center of gravity is often misunderstood: while the faith originated in the Arabian Peninsula, the country with the largest Muslim population today is Indonesia, followed by Pakistan, India, and Bangladesh, making South and Southeast Asia home to more Muslims than the Middle East and North Africa combined.