We began with a Roman empire which commanded the Mediterranean and its resources and wed them to its capitals and armies. In so doing, it bound together Europe, far western Asia, and northern Africa. Subsidized by the state, great fleets of ships moved mountains of goods across the inland sea. In their holds sailed the grain and oil that were the tribute of empire. Subaltern to the north, the southern rim of the Mediterranean, for small profits, sent its wealth across the sea in a tax-powered exchange. As the economy of the western regions of the empire went south, figuratively and literally, the eastern and southern regions took up the slack and bounded further ahead. Eastern merchants aboard eastern ships played an ever greater role in an ever shrinking western economy.

We ended on the far side of a series of transformations, some violent, some silent. As the sequence of shocks which began with bubonic infection subsided, the most dynamic, Middle Eastern engines of the late Roman economy were firing up again. This time, however, the eastern Mediterranean and Africa were fused to the economies of western Asia and the Indian Ocean. Signs of expansion also gathered strength in northwest Europe. By 800, multiple circuits were connecting again, linking the growing agrarian economies and political societies of western Europe to each other, and back to the Middle East. Only this time the ships and traders were mostly western.