What was the predominant religion in the 18 hundreds?

Answer 1

The 1800's were a time of rationalism and religous skepiticism. Even though many people were Christian, the older forms of Christianity, were under attack . Also the great christian missionary movements of the later 1800's had not yet added many adherents. Islam was in a period of decline as well and represented some countries in Africa and the Middle East, with lesser populations. Many countries followed older unorganised superstitions. Some countries in the far east were influenced by Buddhism, but it had not grown to be accepted by the majority of any of these countries. For example, India was mostly Hindu. Given the lack of any other major movements, christianity, was the most influential, but no one religion predominated over the whole world at this time.