There were a great many different religions followed in the ancient
and medieval time periods. Some of them are still practiced today;
others are not. It is hard even to know what religion is, but we see
religion as any tendency to change your own behavior in accordance
with supernatural forces.
Most people in the ancient and medieval world believed that there were many unseen spirits affecting how things happened. The earlier faiths all thought that there were many gods, each responsible for different things: a god of the sky, a god of water, a god of love, and so forth. Egyptian, Sumerian, Chinese, Indian, African, Greek, Roman, and German religions all had their gods organized this way, even though they had different gods. This is called polytheism (poll-ee--THEE-is-em).
But, beginning about 1350 BC in Egypt, there was a movement toward monotheism, or just believing in one god (often with a lot of weaker helper gods or angels). Akhenaten, an Egyptian pharaoh, may have been one of the first powerful people to push this idea. By 1100 BC or so (maybe), we see the Jews practicing monotheism.
In the first century AD, Christianity
began to spread monotheism
to the Mediterranean and Europe, although Judaism
suffered from the Roman
conquest of Jerusalem. By the 500s AD, Buddhism
spread all over China. And
in the 600s AD, Islam replaced
Christianity and Zoroastrianism
as the main religion followed in the Mediterranean,
West Asia, and much of Africa.
By the 1200s, Islam had reached India
(with Egyptian Religion)
West Asian Religion
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