of cavalry brought a change in clothing all over China, for the former
long skirt-like garb could not be worn on horseback. Trousers and the
riding-cap were introduced from the north.

The new technique of war made it important for every state to possess as
many soldiers as possible, and where it could to reduce the enemy's
numbers. One result of this was that wars became much more sanguinary;
another was that men in other countries were induced to immigrate and
settle as peasants, so that the taxes they paid should provide the means
for further recruitment of soldiers. In the state of Ch'in, especially,
the practice soon started of using the whole of the peasantry
simultaneously as a rough soldiery. Hence that state was particularly
anxious to attract peasants in large numbers.

2 _Economic changes_

In the course of the wars much land of former noblemen had become free.
Often the former serfs had then silently become landowners. Others had
started to cultivate empty land in the area inhabited by the indigenous
population and regarded this land, which they themselves had made
fertile, as their private family property. There was, in spite of the
growth of the population, still much cultivable land available.
Victorious feudal lords induced farmers to come to their territory and
to cultivate the wasteland. This is a period of great migrations,
internal and external. It seems that from this period on not only
merchants but also farmers began to migrate southward into the area of
the present provinces of Kwangtung and Kwangsi and as far as Tonking.

As long as the idea that all land belonged to the great clans of the
Chou prevailed, sale of land was inconceivable; but when individual