Overview

Water, one of the basic necessities for human life, was the lifeblood of early civilization. Indeed, the ability of ancient societies to harness the power of water facilitated the rise of agriculture and the first urban centers. So important was water to these early people that historians refer to these first societies as "River Valley Civilizations."

Background

The primary characteristic of these advanced societies was their reliance on sedentary agriculture in which people farmed the same land for generations. The combination of rich soil, mild climate, and a reliable source of water gave ancient people the ability to create crop surpluses. This movement away from nomadic wandering to a more localized existence is known as the Neolithic Revolution. It began about 8,000 years ago in the lush, fertile land surrounding the Tigris, Euphrates, Nile, Indus, and Huang He...