Long time ago, Tibet was an area with a warm, humid climate of subtropical zone of grassland with low altitude which provided a profitable condition for ancient human beings who lived and multiplied in this land. The scientific survey shows that the ancient human being inhabited in Tibet. The earlier cultural remains were mainly discovered in the west and north of Tibet.
Before the 7th century AD, there were many tribes in Tibet. Wars broke out as the tribes tried to expend their territories. Among them, the Tubo tribe owned a large number of lands in Yarlung Valley at its flourishing period. The earliest capital city of Tubo was in the present day Nedong County of Shannan. After Namri Songtsen, the thirty-second generation of Tubo prince inherited the power. He fortified and developed the Tubo’s territory. Songtsen moved the capital from Nedong to Gyama area, today’s Medro Gongkar County. Later in order to refrain from the interior opposite influence between the tribes, Namri, and built the Gyama palace. In the early 7th century AD, Songtsan Gampo, the son of Namri Songtsen, inherited the power, he completed his father’s cause and realized the unification of the Tibet plateau and set up the central slave regime---the Tubo Kingdom.
In order to consolidate the newly emerging power, Songtsen Gampo adopted a series of important measures. In the year of 633 AD, he moved the capital of Tubo Kingdom to Lhasa, built the Potala palace on the summit of the Red Hill and rebuilt the road and some other houses around the Potala palace. Step by step, Lhasa had become economic, political and cultural center of the Tubo Kingdom. To consolidate his regime, Songtsan Gampo advocated the advanced methods of the Tang Dynasty and set up system for civil and military officials, appointed the officials to control the garrisons in other areas and delimited the administrative regions etc. He divided the administrative areas into 18 big areas and established five big 'Ruchen' (Ru is Tibetan pronunciation at the time). Every Ruchen was divided into; upper and lower parts of Ru; every branch of "Ru" had 5000 families who are the common herdsman in peacetimes, but soldiers at war times. Meanwhile, he strengthened the system of discussing official business in alliance. He also remitted taxes, developed agricultural production and promoted economic prosperity. He sent people to ancient India to learn scripts and created the Tibetan written language and calendar and made great contribution to develop the Tubo’s culture.
During Songtsen Gampo’s time, the development of the Tubo Kingdom came to a period of great prosperity. In order to develop the relationship between Tubo and the neighboring countries, he sent the envoys to Nepal firstly and then to the Tang’s court of China to make an offer of marriage in one hand. And at the same time, he used his own armed strength to expand his territories steadily. With his territories expanding Guhuei to the north, he made an expedition to the west till they reached the four towns such as Gueizi, Yutian, Yianqi etc, where it connects with Nanzhuo, Dasi countries to the east. The Tubo kingdom had become the strongest military power in the west of China since the Qin and Han Dynasties.
Songtsen Gampo is the most important and well-known king of Tibet in Tibetan history. In 650 AD, Songtsen Gampo died of illness. The Tubo Kingdom gradually declined because Trisong Detsan, the king of Tibet used force to fight against outside and went in for a large-scale construction and increased the heavy load of the people. He sharpened the social contradiction and led to successive turmoil. In 823 AD, Tibet was in a turbulent situation because the aristocrats in the interior of the Tubo Kingdom fought for their power with each other. The slaves launched a large-scale uprising. Therefore, the Tubo Kingdom was thoroughly collapsed from then on.
In the Yuan Dynasty, Tibet was officially incorporated into China’s territory and finished the long term divisive situation in the interior of Tibet. The Tibetan people obtained the steady life. In the Ming and Qing Dynasty, the central government of China strengthened its administrative grip on Tibet. In recent years, the Tibetan people together with the Chinese people of all nationalities fought against the imperialist invasion and upheld the unified motherland of China.
In May 23, 1951, the Central Committee of People’s Government and the local government of Tibet reached to an agreement –“the 17 Point Agreement on Measures of the Peaceful Liberation of Tibet.” In February 1952, the Military Area of Tibet was officially set up. In April 1956, the Tibet Autonomous Region was established.