From ancient times, the inhabitants of the Qinghai-Tibet Plateau have exchanged visits with the people of the Central Plains. Excavations in Karo started in 1978 have revealed primitive villages, and archaeological finds such as stones axes, adzes, spades, hoes and knives very much akin to those unearthed at Neolithic settlements in the Yellow River valley. Ethnologists and archaeologists agree that the remains excavated in Karo prove that the aborigines of Tibet and the Han nationality of the Yellow River valley had contacts prior to four thousand years ago, which have continued up to the present.

Relations between the Tibetans and China抯 various nationalities, particularly the Han, became closer and closer, especially from the start of the Tang Dynasty (618 AD).

In 641, the Tang Emperor Taizong gave the hand of Princess Wencheng of the Tang court in marriage to the Tsanpo of the Tubo Dynasty, Songtsan Gampo. This policy of alliance by the Tang Dynasty played a positive role in promoting unity, expanding exchanges and enhancing understanding and friendship between nationalities, as well as serving to improve the relation-ship between the Tang Dynasty and the Tubos. The "Marriage alliance" meant that Songtsan Gampo and his successors all acknowledged that their relationship with the Tang Emperors was nephew and uncle.

Emperor Taizong died in 649 and was succeed-ed by Emperor Gaozong who conferred on Songtsan Gampo the titles "Fuma Duwei"and "Prince of the Western Region" In return, Songtsan Gampo sent an envoy with condolences and a memorial expressing loyalty to the Tang Dynasty. Emperor Gaozong then offered him the additional title of "Precious King" and had a stone statue carved for him. Later, in 710, Emperor Zhongzong gave the hand of his adopted daughter Princess Jincheng in marriage to the Tubo Tsanpo Tride Tsugtan.

Princess Jincheng was a lover of literature and art, and brought with her to Tibet many ancient books and records of the arts and crafts, as well as musicians and acrobats. The Tubo Tsanpo cleared the way for her journey, and built a palace in Lhasa to receive her. Princess Jincheng's marriage to the Tibetan king was another great contribution to the development of friendship between the Hans and Tibetans. As a consequence, friendly visits between the Tangs and Tubos increased from then on, and the civilization of the Central Plains became widely known in Tibet.