The very first civilizations appeared in Mesopotamia, between the Tigris and Euphrates rivers, and in Egypt, along the Nile River, between 4000 and 3000 BC. Common to all early civilizations was the belief that the forces of nature were greater and more powerful than those of mortal humans. Of primary importance were those forces that humans relied on most for survival, such as the sun and rain. Although all of the early civilizations shared this same viewpoint, belief systems and religious practices differed dramatically from one civilization to another. However, all systems and practices were meant to help the humans come to terms with such unknowns as the origins of life, the cycle of life and death, and their ultimate destiny and reason for their existence. .
Ancient Egypt thrived out of the banks of the Nile River in northeast Africa. Many villages began to form along the river and depended on its annual overflow which left fertile layers of rich silt along the banks. Egyptian's found security in the Nile's 365-day cycle of inundation and Egypt's perimeter of sea and desert made it relatively invulnerable to foreign invasion, and contributed to its 3,000 years of uniform religious, political, and cultural life. .
Unlike the Egyptians, who relied upon the Nile's predictable overflow, the two rivers surrounding Mesopotamia overflowed without warning, often destroying whole villages and cities. In contrast to Egypt's natural perimeter of sea and desert that eluded invasion, Mesopotamia's exposed plains gave way to repeated attacks. While Egypt enjoyed a mostly hot, arid climate suitable for agriculture, Mesopotamia suffered from the fierce weather changes, including drought, violent rainstorms, flood, wind, and hail.
Both civilizations (except for the Hebrews) had a polytheistic belief system that associated their gods and goddesses with that of nature and its forces. However, like Mesopotamia's unstable climate, its gods were fierce and capricious, unlike Egypt's, who played protective roles for the Egyptians.
