Christianity is practiced as the majority religion in most regions of the world except for North Africa, the Middle East, India, China and Southeast Asia, according to Maps of the World. There are more than 2.18 billion Christians in the world and nearly of half of them live in 10 countries. The Pew Research Religion and Public Life Project reveals the country with the most Christians is the United States.
Demographically, more than 51 percent of Americans are Protestant Christian, as of 2014. Nearly 24 percent of Americans identify themselves as Catholic. These two major Christian sects account for more than three-fourths of the American population. More than 16 percent of Americans claim they are unaffiliated with one particular religion.
Following the United States in descending order of Christian population is Brazil, Mexico, Russia, The Philippines, Nigeria, China, The Democratic Republic of Congo, Germany and Ethiopia. China makes the top 10 despite Buddhism being the predominant religion, yet there are more than 67 million Christians in China out of more than 1.3 billion total people. The top 10 majority-Christian countries account for 1.04 billion Christians out of 2.18 billion worldwide.
Pew Research notes Christianity flourished far away from its origin point. There are a mere 13 million Christians in the Middle East and North Africa where Christianity started, the lowest Christian population of any region on Earth. Indonesia, a Muslim-majority country, has more Christians than all 20 countries in the Middle East and North Africa combined.