Some 1300 years ago,Princess Wencheng of the Tang Dynasty (618-907) left Chang'an (present-day Xi'an in Shanxi Province) to marry Songtsan gambo, king of the Tubo kingdom, which was located about 3000 km to the west. This pioneered amicable relations between the Tang and the Tubo,and the story of the marriage is still much talked about in areas inhabited by the Han and Tibetan peoples.

In the early 7th century, Li Yuan (later Emperor Gaozong of the Tang Dynasty) and Li Shimin (son of Li Yuan and later Emperor Taizong of the Tang Dynasty) unified the Central Plains and founded the Tang Dynasty, setting the capital at Chang'an.The Tang was formidably powerful, and became the civilizational center of East Asia. Neighboring nations and tribes fell under the influence of the Tang Dynasty,and earnestly sought ties with the dynasty. They either claimed allegiance to the Tang or paid tributes to the imperial court. This stimulated exchanges between the Han and other nationalities.

The same period saw Songtsan Gambo gain control of the highland area in the west. After having annexed some tiny states, he founded the Tubo Kingdom and named Loso (present-day Lhasa) the capital city. Beginning in 634, he twice dispatched Gar Tongtsan to Chang'an, where the Tubo minister informed the Tang of Songtsan Gambo's desire for a daughter of the Tang emperor. Tang Emperor Taizong agreed to let Wencheng Marry the Tubo king. Accompanied by the Tubo minister, Princess Wencheng set out for the farway Tubo Kingdom. This segment of history was later turned into tales which remain an important part of Tibetan folklore.

Songtsan Gambo was very happy with his success. He went to greet the Tang Princess in Baihai (present-day Madu County in Qinghai Province) at the head of an army. He had the Baihai Nuptial Palace set up by the Zhaling and E'ling lakes, and the couple of different nationalities held their wedding ceremony there.

When the couple moved to Yushu (in present-day Qinghai Province), they were much taken with the local landscapes and pleasant weather, and spent one month in a mountain valley for their honeymoon. Princess Wencheng had carried crop and vegetable seeds to Tibet, and joined her entourage in teaching the local people how to grow crops and vegetables, grind wheat flour and make wine. When the party had to leave, the local people were grieved. As a token of gratitude, the buildings where the Tang princess stayed were still retained in the form of ruins, and her footprints were carved into rocks for worshipping. In 710 when Jincheng, another princess of the Tang Dynasty, was married into the Tubo Kingdom,she passed by the same place and had the Temple of Princess Wencheng built there. Princess Wencheng encountered a dancing and singing party in Lhasa. Seeing that Buddhism,which was at its height of influence in Tang areas, had not been spread into the Tubo Kingdom, Princess Wencheng brought out Buddhist pagodas, scriptures and statues of Buddha which she had brought into the Tubo area for construction of monasteries. Goats were mobilized to carry earth to fill in a pond for the construction of the Jokhang Monastery.Upon complete of the monastery. Princess Wencheng and her husband, Songtsan Gambo, planted willow tree in front of the monastery, which later was dubbed the Tang Willow, as the Uncle-Nephew Alliance Tablet (erected in 823 to mark the alliance between the Tang and the Tubo) was placed next to the tree. The statue of Sakyamuni enshrined in the center of the Main Hall of the Jokhang Monastery was the one Princess Wencheng brought into Tubo. In the side halls flanking the Main Hall are enshrined statues of Songtsan Gambo and Princess Wencheng. Their faces were heavily gilded by incessant worshipers of later generations.

Princess Wencheng also had the Ramoche Monastery built. She named the eight surrouding mountains the Eight Treasures, a name which is still in use today. All these paved the way for the spread of Buddhism into Tubo Kingdom.

While making efforts to propagate Buddhism and pray for blessings for the Tibetans, Princess Wencheng taught them how to grow crops and vegetables. Maize, potatoes, soybeans and rape proved adaptable to the highland enviroment, while wheat mutated into highland barley known in Tibetan as qingke. Princess Wencheng also brought into the Tubo Kingdom carriages, horses, donkeys and camels, as well as medical works and various kinds of farming and industrial techniques. Under her direction, the Tubo Kingdom experienced fast social progress.

Songtsan Gambo loved Princess Wencheng so much that he had the Potala Palace built for his talented and beautiful wife. The majestic Potala Palace, with 1000 chambers, was partially damaged by thunderbolts and wars. It twice underwent repairs and expansions in the 17th century, reaching its present size, with the 13-story main structure standing 117 meters high and covering a land area of 360000 square meters. Frescos of the Potala Palace record historical events, including Tang Emperor Taizong asking Gar Tongtsan to perform five difficult tasks before acceding to the envoy's request for his master to marry a Tang princess, the hardships Princess Wencheng endured on way to the Tubo Kingdom, and how warmly she was greeted at Lhasa.The ruins of the Tubo period behind the Potala Palace includes a chamber for Songtsan Gambo to meditate and practice Buddhism. On the four walls of the chamber hang colored statues of Songtsan Gambo, Princess Wencheng and Gar Tongtsan.

After Princess Wencheng married into the Tubo Kingdom, the Central Plains and the Tubo area maintained close relations for more than 200 years,a period almost free from wars and most notable for its varied cultural and commerical exchanges. Songtsan Gambo showed great interest in the culture prevailing in the Central Plains. He wore silks instead of the felt robes customarily worn in Tibet. Children of Tubo noble families were sent to study in Chang'an. The imperial court of the Tang Dynasty also sent artisans into the Tubo Kingdom, where they taught the local people various kinds of techniques.

The Tang Emperor Taizong (Li Shimin) died in 649. Emperor Gaozong dispatched men to inform Songtsan Gambo of the news, and granted him the official position of "Imperial Son-in-Law Governor" and bestowed upon him the honorific title of "West Sea Prince." Songtsan Gambo sent envoys to Chang'an to mourn the late emperor along with 15 kinds of gold objests for worship at the Tomb of Emperor Taizong and a letter to Emperor Gaozong, in which Songtsan Gambo expressed his support and congratulations to the new Tang emperor. Tang Emperor Gaozong promoted Songtsan Gambo to the position of "Treasured Prince" and had his statue carved and erected in front of the Tomb of Emperor Taizong as a token of praise.

Songtsan Gambo unified Tibet, promoted political, economic and cultural development of his Tubo Kingdom, and strengthened ties between Tibet and Central Plains. In so doing he made outstanding contributions to the unification of the Chinese nation. Princess Wencheng, who married into the Tubo Kingdom and worked to promote economic and cultural exchanges between the Central Plains and the Tubo area, left a historic legacy of friendship and cooperation between the Han and the Tibetan peoples. All these events have been recorded in history books and lie embedded in the minds of the Han and the Tibetan peoples.