The Bronze Age Collapse

From the introduction: The beginning of the Bronze Age heralded the greatness of mankind’s first civilizations: Egypt and Sumer, Akkad and Elam, and many lesser peoples besides. For the first time in history long-distance trade became essential to the workings of human society, and polities greater than primitive city-states began to form. Pharaoh Menes united Egypt during the dawn of this age, and centuries later Sargon of Akkad would build the first empire in history, and from there on the glories and horrors of war would only expand in scope and reach.