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 of a long gradual process that would transform the ancient world of classical antiquity into the medieval one of the Early Middle Ages.