The temples were the most important type of building, and the main religious beliefs were that there was a physical embodiment for everything in nature, and for things such as weather, natural disasters, and other things they couldn't explain.
The importance of handwashing
Cofussionism & Buddhism
For exactly the same reasons that people who hold religious beliefs today think their god is important
well there are somethings tht tell us about religious beliefs in the ancient and modern Olympics which are all competitors are from there country they were born in and they are competing for tht country what ever religious beliefs they might have!
Government/religion/beliefs
they believed in polytheism (many gods)
Polytheism; nature religions--
Ancient Greek does not have a word for religion. The Greek based word theology is the study of beliefs about god or religious beliefs.
The Nile River fits your description. It was so important to the Ancient Egyptians that it became a part of their Religious beliefs. They called the Goddess of the Nile, Anuket.
Greek gods. The ancient Greeks believed in gods that lived on mt Olympus.
The hebrews
Islam is the most important and it will always be extremly important