China had received with more or less good grace the flood of Buddhist missionaries but had long since sent out her own missionaries— priests, not of a transcendental religion of salvation, but of a secular way of life, of a worldly and refined civilization. Expansion in Turkestan and Central Asia took place simultaneously with expansion in Southeast Asia. As fast as the famed Silk Road started winding itself through thousands of miles of Eurasian deserts, swamps, jungles and mountains toward Persia and the Mediterranean world, increasingly numerous fleets of junks began to ply the warm waters of the tropical south.
Source: wiktionary