goods. This resulted in a great deal of economic interdependence among the empire's inhabitants. The historian Henry St. Lawrence Beaufort Moss describes the situation as it stood before the crisis: With the onset of the Crisis of the Third Century, however, this vast internal trade network broke down. The widespread civil unrest made it no longer safe for merchants to travel as they once had, and the financial crisis that struck made exchange very difficult with the debased currency. This produced profound changes that, in many ways, foreshadowed the very decentralized economic character of the coming Middle Ages. Large landowners, no longer able to successfully export their crops over long distances, began producing food for subsistence and local barter. Rather than import manufactured goods from the empire's great urban areas, they began to manufacture many goods locally, often on their own estates, thus beginning the self-sufficient "house economy" that would become commonplace in later centuries, reaching its final form in the manorialism of the Middle Ages. The common, free people of the Roman cities, meanwhile, began to move out into the countryside in search of food and better protection. Made desperate by economic necessity, many of these former city dwellers, as well as many small farmers, were forced to give up hard-earned basic civil rights in order to receive protection from large land-holders. In doing so, they became a half-free class of Roman citizen known as coloni. They were tied to the land, and in later Imperial law, their status was made hereditary. This provided an early model for serfdom, the origins of medieval feudal society and of the medieval peasantry. The decline in commerce between the imperial provinces put them on a path toward increased self-sufficiency. Large landowners, who had become more self-sufficient, became less mindful of Rome's central authority, particularly in the Western Empire, and were downright hostile toward its tax collectors. The measure of wealth at this time began to have less to do with wielding urban civil authority and more to do with controlling large agricultural estates in rural regions since this guaranteed access to the only economic resource of real value – agricultural land and the crops it produced. The common people of the empire lost economic and political status to the land-holding nobility, and the commercial middle classes waned along with their trade-derived livelihoods. The Crisis of the Third Century thus marked the beginning