They had even had some experience of Christianity; for Nestorian Missions existed in Central Asia in the fifth and sixth centuries of our era, and penetrated to China in the seventh century. All these religions strove to convert the Mongolians, who soon became an important nation through the conquests of Jenghiz Khān. That conqueror, however, had a very simple religion of his own. He believed in one God in heaven, and one king on earth; that is, he believed that God had given him the dominion of the whole world, and he set himself to conquer the world. Yet he tolerated all religions. ‘As the hand,’ he said, ‘has many fingers, so there are many ways to show men how they may reach heaven.’
Khubilai (1259-1294), the greatest of all the descendants of Jenghiz and Sovereign of a vast empire, was the first to elevate his people above a mere life of rapine and plunder; and it struck him that the best method of civilizing them would be by adopting and promoting Buddhism, which the greater number of the races subject to him already professed.
Between the indigenous Shamanism of Northern countries and the doctrines of Confucius, or of Islām, or of Christianity, there were no points of contact; whereas Shamanism, as we have seen, had much common ground with Northern Buddhism, which had become mixed up with Ṡaivism and magic.
It was this that led Khubilai to adopt the Lāmistic or Tibetan form of Buddhism. He also thought it wise to conciliate the spiritual potentates of Tibet, who had for many centuries taken all real power out of the hands of their temporal chiefs.
And among Lāmistic prelates, the Head of the Monastery of Sakya and of the Red school in Southern Tibet had, as we have seen, acquired a kind of sovereignty. Many monks of this Red sect married, according to the practice of the Brāhmans, and remained householders till a son and heir was born to them. At that time they had a presiding monk, called Sakya Paṇḍita, and the Emperor Khubilai appointed Mati-dhvaja, the Paṇḍita’s nephew, to succeed him as Head of the monastery, conferring on him a certain amount of temporal power and making him a kind of tributary ruler of Tibet. He was known as the Phaspa (strictly Phags pa), ‘excellent Lāma,’ and in return for the supremacy granted to him, was required to consecrate or crown the emperors of Mongolia.
Koeppen observes that Khubilai was thus the creator of the first Lāmistic Pope; just as Pepin and Charlemagne were of the first Christian Pope.
The Mongolians also owe their written character and literature to Buddhism. It was Phaspa Lāma who invented the Mongolian alphabet. Taking the Tibetan alphabet as his model, he invented a square character with a thousand syllables. He then undertook a new revision of the Buddhist sacred writings, causing the Tibetan sacred texts (Kanjur) to be compared with the Chinese. It is said that this lasted from the year 1285 to 1306.
Twenty-nine learned men, versed in the Tibetan, Ugrian, Chinese, and Sanskṛit languages, were occupied on the task of collation, and a few years later, the first Mongolian translation of the sacred texts was begun by the Sakya Lāma Ćhoskyi Odser.
Khubilai, no doubt, was a great promoter of Buddhism, and founded many monasteries in Mongolia, and a celebrated one at Peking.
After the elevation of the Phaspa Lāma to quasi-temporal as well as spiritual sovereignty very little is known about the state of Buddhism in Tibet, except that the successive Heads of the Sakya monastery maintained their position under Khubilai’s successors, and of course perpetuated and extended the doctrines of the Red school of Buddhism. Probably they resided at Lhāssa, and possibly at the Mongolo-Chinese Court.