abandonment of agriculture brought them into a precarious situation: if
for any reason the Chinese stopped supplying or demanded excessive
barter payment, the nomads had to go hungry. They were then virtually
driven to get what they needed by raiding. Thus there developed a mutual
reaction that lasted for centuries. Some of the nomadic tribes living
between garrisons withdrew, to escape from the growing pressure, mainly
into the province of Shansi, where the influence of the Chou was weak
and they were not numerous; some of the nomad chiefs lost their lives in
battle, and some learned from the Chou lords and turned themselves into
petty rulers. A number of "marginal" states began to develop; some of
them even built their own cities. This process of transformation of
agro-nomadic tribes into "warrior-nomadic" tribes continued over many
centuries and came to an end in the third or second century B.C.

The result of the three centuries that had passed was a symbiosis
between the urban aristocrats and the country-people. The rulers of the
towns took over from the general population almost the whole vocabulary
of the language which from now on we may call "Chinese". They naturally
took over elements of the material civilization. The subjugated
population had, meanwhile, to adjust itself to its lords. In the
organism that thus developed, with its unified economic system, the
conquerors became an aristocratic ruling class, and the subjugated
population became a lower class, with varied elements but mainly a
peasantry. From now on we may call this society "Chinese"; it has
endured to the middle of the twentieth century. Most later essential
societal changes are the result of internal development and not of
aggression from without.

4 _Limitation of the imperial power_