military control, had brought China inner stability and in consequence
external power and prestige. The reputation which she then obtained as
the most powerful state of the Far East endured when her inner stability
had begun to deteriorate. Thus in 638 the Sassanid ruler Jedzgerd sent a
mission to China asking for her help against the Arabs. Three further
missions came at intervals of a good many years. The Chinese declined,
however, to send a military expedition to such a distance; they merely
conferred on the ruler the title of a Chinese governor; this was of
little help against the Arabs, and in 675 the last ruler, Peruz, fled to
the Chinese court.

The last years of T'ai Tsung's reign were filled with a great war
against Korea, which represented a continuation of the plans of the Sui
emperor Yang Ti. This time Korea came firmly into Chinese possession. In
661, under T'ai Tsung's son, the Korean fighting was resumed, this time
against Japanese who were defending their interests in Korea. This was
the period of great Japanese enthusiasm for China. The Chinese system of
administration was copied, and Buddhism was adopted, together with every
possible element of Chinese culture. This meant increased trade with
Japan, bringing in large profits to China, and so the Korean middleman
was to be eliminated.

T'ai Tsung's son, Kao Tsung (650-683), merely carried to a conclusion
what had been begun. Externally China's prestige continued at its
zenith. The caravans streamed into China from western and central Asia,
bringing great quantities of luxury goods. At this time, however, the
foreign colonies were not confined to the capital but were installed in
all the important trading ports and inland trade centres. The whole
country was covered by a commercial network; foreign merchants who had
come overland to China met others who had come by sea. The foreigners