Slavery, which had been a rising and sporadic factor in the preceding stage, now became an essential part of the social system. The slaves ceased to be simple assistants. They were now driven in scores to the work in the fields and shops. The division of production into two great branches, agriculture and handicrafts, gave rise to production for exchange, the production of commodities. Trade arose at the same time, not only in the interior and on the tribal boundaries, but also in the form of maritime exchange. All this was as yet in a very undeveloped state. The precious metals gained preference as a universal money commodity, but still uncoined and exchanged merely by dead weight.
The distinction between rich and poor was added to that between free men and slaves. This and the new division of labor constitute a new division of society into classes. The differences in the amount of property belonging to the several family heads broke up the old communistic households one by one, wherever they might have been preserved thus far. This made an end to the collective cultivation of the soil for the account of the community. The cultivated land was assigned for use to the several families, first for a limited time, later for once and all. The transition to full private property was accomplished gradually and simultaneously with the transition from the pairing family to monogamy. The monogamous family began to be the economic unit of society.
The increase of population necessitated a closer consolidation against internal and external foes. The federation of related tribes became unavoidable. Their amalgamation, and thence the amalgamation of the separate tribal territories to one national territory, was the following step. The military leader—rex, basileus, thiudans—became an indispensable and standing official. The public meeting was introduced wherever it did not yet exist. The military leader, the council of chiefs, and the public meeting formed the organs of the military democracy that had grown out of the gentile constitution. Military democracy—for now war and