The archeological discoveries prove that the history of Tibet can be traced many thousand years back. However, the written history only dates back to seventh century when the thirty-third king, Songtsan Gampo realized the importance of scripts and sent his wise minister Sambhota to India to study Sanskrit. The minister on his return invented the present Tibetan script.
Nyetri Tsanpo was the first king recorded academically. It is recorded that a group of Tibetan recognized a young man to be the king and carried him on their shoulder in 127 B.C and the king dynasty ended in 847 A.D when the last king, Lang Dharma intended to desalinate the Buddhism believed and followed by Tibetan people. Of all the kings, Songtsan Gampo is considered as the most outstanding king.
Tibet started to become weak after the assassination of King Lang Dharma. The once united state became decentralized and many more small powers emerged in different part of Tibet. Hence, there is a little historical documents are available for us to study the decentralized period. The power popular story known to the world is the abbot of Sakya monastery became a vassal of Kublai Khan.
The Mongolian power had a quite long influence in Tibet. The influence of the Mongolian power last for about four hundred years and ended in 1642 A.D. For those four hundred years, the political power to rule Tibet was offered to Sakya sect.
The fifth Dalai Lama is considered one of the greatest leaders in the history of Tibet. The fifth Dalai Lama overtook the power from Tsang and consolidated the power. The fifth Dalai Lama had all his effort to make a greater Tibet and introduction of Ganden Podrang administration was formed where political and spiritual power was integrated.
Note: The Mongolian script was invented by the Sakya abbot during Yuan dynasty.