Around 700 ad, Songsan Gampo, king of Tubo (old name for Tibet), sent messenger to Chang'an, capital of Tang Dynasty,
asking the Chinese emperor for the hand of his daughter, princess Wencheng. There are many legends of this meeting,
that the messenger was a intelligent man and solved the puzzles from the emperor and finally defeated other messengers and persuaded the princess to marry to Tibet.
This painting is about this meeting.
The marriage has a deep influence on Tibet. Princess Wencheng brought the golden Statue of Buddha at age of 12 to Lhasa, and helped bulding the temples there, among them the Jokhang.

The second man from the left is the Tibetan messenger.