From The Wall Street Journal:
It’s hard to imagine a world without rivers. The continents would be higher, colder and more rugged, and we humans might still be hugging the coastlines. Our iconic cities, situated along rivers, would not have been built. Global trade and travel might never have developed. Even so, rivers’ crucial role in shaping civilization is “grandly underappreciated,” according to Laurence C. Smith, professor of earth, environmental and planetary sciences at Brown University. In his important new book “Rivers of Power,” he surveys mankind’s long, shifting relationship with our rivers, ranging from prehistory to the present and embracing nearly every region of the world.
Rain started falling on Earth at least 4 billion years ago. Merging into streams and then rivers, the water launched its eternal assault on the continents, grinding them down and carrying them grain by grain toward the sea. The rivers, over their tortuous course, occasionally slowed and dropped some of their silt, forming tangled deltas and wide valley plains. Perhaps as recently as 12,000 years ago, nomadic peoples in the Mideast and Asia settled these valleys and began to plant crops such as wheat, barley and rice.
The valley soil was fertile, and early farmers learned to divert river water for irrigation, increasing their harvests and producing surpluses of grain. Starting about 4,000 B.C., they built the world’s first great cities, in present-day Iraq, Egypt, India, Pakistan and China. As these societies grew wealthier and more populous, they also became more complex, supporting a ruling class, traders, philosophers and engineers. In fact, these civilizations (the Egyptian, Sumerian, Harappan and Chinese) were so utterly dependent on their rivers (the Nile, Tigris and Euphrates, Indus and Ghaggar-Hakra, and Yangtze and Yellow) that they have been dubbed “hydraulic societies.”
Link to the rest at The Wall Street Journal (PG apologizes for the paywall, but hasn’t figured out a way around it.)