It is curious that the early history of Burma should be so obscure and in order not to repeat details and hypotheses I refer the reader to the chapter dealing specially with this country. From an early epoch Upper Burma had connection with China and Bengal by land and Lower Burma with Orissa and Conjevaram by sea. We know too that Pali Buddhism existed there in the sixth century, that it gained greatly in power in the reign of Anawrata (c. 1060) and that in subsequent centuries there was a close ecclesiastical connection with Ceylon.
Siam as a kingdom is relatively modern but like Burma it has been subject to several influences. The Siamese probably brought some form of Buddhism with them when they descended from the north to their present territories. From the Cambojans, their neighbours and at one time their suzerains, they must have acquired some Hinduism and Mahayanism, but they ended by adopting Hinayanism. The source was probably Pegu but learned men from Ligor were also welcomed and the ecclesiastical pre-eminence of Ceylon was accepted.
We thus see how Indian influence conquered Further India and the Malay Archipelago and we must now trace its flow across Central Asia to China and Japan, as well as the separate and later stream which irrigated Tibet and Mongolia.
Tradition as mentioned ascribes to Asoka some connection with Khotan and it is probable that by the beginning of our era the lands of the Oxus and Tarim had become Buddhist and acquired a mixed civilization in which the Indian factor was large. As usual it is difficult to give precise dates, but Buddhism probably reached China by land a little before rather than after our era and the prevalence of Gandharan art in the cities of the Tarim basin makes it likely that their efflorescence was not far removed in time from the Gandharan epoch of India. The discovery near Khotan of official documents written in Prakrit makes colonization as well as religious missions probable. Further, although the movements of Central Asian tribes commonly took the form of invading India, yet the current of culture was, on the whole, in the opposite direction. The Kushans and others brought with them a certain amount of Zoroastrian theology and Hellenistic art, but the compound resulting from the mixture of these elements with Buddhism was re-exported to the north and to China.
I shall discuss below the grounds for believing that Buddhism was known in China before A.D. 62, the date when the Emperor Ming Ti is said to have despatched a mission to enquire about it. For some time many of its chief luminaries were immigrants from Central Asia and it made its most rapid progress in that disturbed period of the third and fourth centuries when North China was split up into contending Tartar states which both in race and politics were closely connected with Central Asia. Communication with India by land became frequent and there was also communication via the Malay Archipelago, especially after the fifth century, when a double stream of Buddhist teachers began to pour into China by sea as well as by land. A third tributary joined them later when Khubilai, the Mongol conqueror of China, made Lamaism, or Tibetan Buddhism, the state religion.