On afrigid night over six decades ago, as artillery fire echoed in the distance and Chinese forces encircled the Tibetan capital of Lhasa, a 23-year-old monk disguised as a soldier slipped quietly out of his palace.

The Dalai Lama turned 90 on Sunday surrounded by thousands of followers, who thronged the Himalayan town of Dharamshala, where the spiritual leader of Tibetan Buddhism has been living in exile since fleeing Chinese rule in Tibet in 1959.

Today, he’s a frail 90. But in March 1959, in his early 20s, the 14th Dalai Lama undertook perhaps one of the most difficult journeys of his lifetime — fleeing Tibet under the cover of darkness, disguised as a soldier,