the empire. The extremely sanguinary wars had brought fearful suffering
upon the population. During the years of the rising, no taxes came in
from the greater part of the empire, but great sums had to be paid to
the peoples who had lent aid to the empire. And the looting by
government troops and by the auxiliaries injured the population as much
as the war itself did.

When the emperor Su Tsung died, in 762, Tengri, the khan of the Uighurs,
decided to make himself ruler over China. The events of the preceding
years had shown him that China alone was entirely defenceless. Part of
the court clique supported him, and only by the intervention of P'u-ku
Huai-en, who was related to Tengri by marriage, was his plan frustrated.
Naturally there were countless intrigues against P'u-ku Huai-en. He
entered into alliance with the Tibetan T'u-fan, and in this way the
union of Turks and Tibetans, always feared by the Chinese, had come into
existence. In 763 the Tibetans captured and burned down the western
capital, while P'u-ku Huai-en with the Uighurs advanced from the north.
Undoubtedly this campaign would have been successful, giving an entirely
different turn to China's destiny, if P'u-ku Huai-en had not died in 765
and the Chinese under Kuo TzÅ­-i had not succeeded in breaking up the
alliance. The Uighurs now came over into an alliance with the Chinese,
and the two allies fell upon the Tibetans and robbed them of their
booty. China was saved once more.

Friendship with the Uighurs had to be paid for this time even more
dearly. They crowded into the capital and compelled the Chinese to buy
horses, in payment for which they demanded enormous quantities of
silkstuffs. They behaved in the capital like lords, and expected to be
maintained at the expense of the government. The system of military
governors was adhered to in spite of the country's experience of them,