Later, with the support of his uncle Lun Keer and Prime Minister Shang Bao, Songzan Gambu eliminated the internal rebellion after three years of repression. In 632 AD, he led the people across the Yarlung Zangbo River and moved the capital to Luoluo (Lhasa).
Songtsan Gambo recruited Toarey Yang, killed King Toarey Yang, and incorporated the vast area and people of Toarey Yang into Tubo. As a result, Songzan Gambo unified Tibet and established a powerful Tubo kingdom.
At the same time, in Chang 'an, thousands of kilometers away from Lhasa, the Tang Dynasty also achieved unprecedented development under the rule of Li Shimin, creating a famous "Zhenguan rule" in history. The prosperous Tang dynasty also had a powerful shock to the surrounding tribes, and an unprecedented grand occasion of "all nations coming to Korea" appeared. Therefore, Li Shimin is honored as "Tiankhan" by all tribes.
Song Zan Gambu admired the famous Tang Dynasty for a long time, so he came up with an idea that had a far-reaching influence on later generations: he wanted to marry the Tang Dynasty and its princess.
Songzan Gambu sent a messenger thousands of miles to Chang 'an to propose to Datang, but Li Shimin politely refused. After the messenger returned to Lhasa, he explained to Songzan Gambu the reason for the failure of the proposal, because King Tuyuhun was in the way.
Songzan Gambu, whose self-esteem was seriously damaged, decided to use force to crusade against Tugu Hunbu and attack Songzhou, the border of Datang. The war continued, deadlocked. Finally, relying on surprise attack, Tang Jun defeated the Tubo army and forced Songzan Gambu to retreat.
The defeated Songzan Gambu once again sent Prime Minister Lu Dongzan to Chang 'an to propose to Datang. Li Shimin didn't want to rekindle the war in the frontier, so he agreed to Songzan Gambu's request and ordered Princess Wencheng and pro-Tubo.
Princess Wencheng is actually just a royal daughter. There is no record of her life history. Historians believe that Princess Wencheng should be the daughter of Li Daozong, the king of Jiangxia County.
Li Shimin appointed Li Daozong as an envoy to escort Princess Wencheng to Rogge. Songzan Gambu "greeted Heyuan personally, met Daozong, and paid his son-in-law a very respectful ceremony". This shows that Songzan Gambu attaches great importance to this princess of Datang.
As the number one power in the world at that time, Li Shimin gave Princess Wencheng a very generous dowry. Apart from a dazzling array of jewels, gold and silver antiques and various books, the most precious one is a statue of siddhattha gotama aged 12. This Buddha statue is still enshrined in Jokhang Temple and has become a holy Buddha that Tibetan Buddhist believers yearn for and worship all their lives.
After Princess Wencheng entered Tibet, she was greatly treated by Songzan Gambu. He not only crowned Princess Wencheng himself, but also made her a queen, ranking first among all princesses. At the same time, a palace was specially built for Princess Wencheng. The murals in the palace described in detail the difficult course of Princess Wencheng's entry into Tibet and the unprecedented courtesy she received after arriving in Lhasa.
Songzan Gambu also ordered people to build colorful statues of Princess Wencheng in Zhao temples, large and small, for Tibetans to worship.
Of course, Princess Wencheng also brought the culture and advanced technology of the Tang Dynasty, such as cooking, textile, medicine, sericulture and so on. So her in-laws are not political marriages in the traditional sense. She not only won an environment of peaceful development for the Tang Dynasty, but more importantly, Princess Wencheng was the first messenger to sow the seeds of the Central Plains culture on the Qinghai-Tibet Plateau and the earliest cultural pioneer on the Qinghai-Tibet Plateau.
After Princess Wencheng entered Tibet, the relationship between Tubo and Datang entered the honeymoon period. Songzan Gambu has always claimed to be a "son-in-law". The two sides exchanged needed goods in the fields of politics, military affairs, culture, commerce and trade, and learned from each other, which made Tibetan and Chinese people become a whole, just like the poem said, "Since your Lord and wife got married, half of Hu Feng is like a Han family."
Princess Wencheng was deeply saddened by the death of Songzan Gambu.
Although she was married by imperial decree and had no love affair with Songzan Gambu before, after nine years of husband and wife life, she deeply fell in love with this talented Zap. Songzan Gambu's untimely death caught her off guard, and made her miserable, and she fell into deep thoughts of her husband for a long time.
Princess Wencheng and Songzan Gambu failed to have children. According to the rules of the Tang Dynasty at that time, the princess could return to Chang 'an after her husband died. However, Princess Wencheng gave up this idea. She wanted to stay in Tibet and continue to contribute to the friendship between Tibetans and Han people for generations.
As a result, Princess Wencheng lived alone in Tibet for 30 years. During this period, she always cared about Tibetans and Tubo, and made great contributions to the economic and cultural development of Tubo.
Princess Wencheng died of smallpox, and Tubo held an unprecedented grand funeral for her, and Datang also sent messengers to mourn for her.
After the princess died, her noble character won the incomparable respect and love of the Tubo people. They built a temple in the place where the princess once lived, dedicated her statue, and worshipped her all the year round in the most respectful way of Tibetans.
In Princess Wencheng's temple, butter lamps never go out all day, incense is flourishing, and the sound fills the air. In the minds of Tubo people, Princess Wencheng is a bodhisattva and a "Buddha" sent by heaven to save them. The story of Princess Wencheng has been adapted into a Tibetan opera, which has been circulated for thousands of years under the majestic snow-capped mountains, making people never tire of watching it.