The moment
Tang histories record that the Chinese princess Wencheng travelled to Tibet around 641 to marry King Songtsen Gampo. Tibetan histories written centuries later credit her and a Nepalese wife, Bhrikuti, with bringing Buddha images and inspiring the Jokhang and Ramoche temples in Lhasa, and credit the king's minister with devising the Tibetan script. Buddhism became the state religion only a century later, under Trisong Detsen.
People: Songtsen Gampo, Princess Wencheng, Bhrikuti