The history of Tibetan Buddhism can be traced back to the latter half of the 2nd century when Thothori Nyantsen was the king of Tibet. During his time, some Buddhist scriptures arrived in southern Tibet from India. The 3rd century saw the spread of scriptures in the northern part of Tibet. At this point of time, Buddhism was not a dominant religion in Tibet but was actually beginning to take shape. The tantric text were yet in the process of being written in India.
King Songtsen Gampo
The first major event in the history of Tibetan Buddhism occured during the reigns of King Songtsen Gampo in 641. During his rule, Tibet was unified and he also married two Buddhist, Princess Wencheng from China and Princess Bhrikuti Devi from Nepal. This was followed by Buddhism being declared as the State Religion. A network of 108 Buddhist temples were constructed so as to facilitate the installation of the Buddha statues his wives had brought from their homes. However, along with all this, conflict with the existing national religion, Bon, too continued for long.
Arrival of Padmasambhava & Atisa
The other major event, or perhaps what can be termed as the most important event in the history of Tibetan Buddhism was the arrival of sage Padmasambhava. He was invited over to Tibet by King Trisong Detsen in th year 774. Padmasambhava translated numerous Buddhist texts into Tibetan language and combined tantric Buddhism with the local Bön religion to create what is today widely known as the Tibetan Buddhism. Apart from these, Padmasambhava also laid down the foundation of the first Tibetan Buddhist School, Nyingma. Subsequently, in the coming years, all the other schools of Tibetan Buddhism arose from this School itself.
By the middle of the 9th century, Buddhism suffered a major opposition from the locals and even the government withdrew its support. It took the arrival of another great Indian scholar, Atisa to restore Buddhism in Tibet. His disciple, Dromton laid down the foundation of yet another old School of Buddhism, Kadampa.
With advent of the 11th century, Tibetan Buddhism became dominant in Central Asia, specially in countries like Mongolia and Manchuria. In both these countries, it was adopted as the State Religion. From 11th century onwards, the other Schools of Tibetan Buddhism, Sakya, Kagyu and Gelug, also started emerging. In the successive centuries, each of these Schools established itself in diiferent parts of Tibet.
Post Chinese Invasion
In the second half of the 20th century, Communist Chinese forces marched into and captured Tibet. They brought about a wave of institutional change thereby making it impossible for many Tibetan spiritual leaders to continue their religious practice in Tibet. These leaders fled their country and took refuge in other countries, the most important one being the Dalai Lama who today resides in the north Indian state of Himachal Pradesh.
Tibetan Buddhism Today
As of today, Tibetan Buddhism is definitely not just confined to Tibet, rather it has spread its wings in the western countries as well. There are a number of followers of Tibetan Buddhism all around America and Europe including the famous celebrities like Richard Gere, Adam Yauch, Allen Ginsberg; Philip Glass, and Steven Seagal. The last one of these has also been infact been declared a tulku (a Tibetan Buddhist lama who decides to be reborn so as to complete his inclomplete tasks).
Apart from the western countries, Tibetan Buddhism has also established its roots in Bhutan, Mongolia, Kalmykia (the Russian north Caucasus), Siberia (central Russia), and the Russian Far East.
