Tibetan attack on Songzhou

Tibetan attack on Songzhou
Date 638 AD Location Sichuan, China Result Tang victory
Location within China

The first military conflict between China and Tibet occurred in 638. In the early 7th century, the westward conquests of the Chinese Tang dynasty brought it into contact with the rising Tibetan Empire. When Emperor Taizong of Tang refused a marriage alliance, the Tibetan emperor Songtsän Gampo sent an army to attack the Chinese frontier city of Songzhou (松州, in modern Sichuan). After a Tang army inflicted heavy casualties on the Tibetans in a night-time attack, Songtsän Gampo withdrew. He sent emissaries and tributes to Chang'an to apologize, and to again request marriage. Taizong decided to give Songtsän Gampo a distant niece, Princess Wencheng, in marriage. The peace held for the remainder of the reigns of Taizong and Songtsän Gampo, although Tibet would pose major military threats for most of the rest of the Tang period.

During the early decades of the 7th century, the major threat to the west of China was the Xianbei state of Tuyuhun. Thereafter, Tuyuhun's southwestern neighbor, the Tibetan Empire, rose in power.

The existence of Tibet was unknown to the Chinese until 608, when Tibetan emissaries from Emperor Namri Songtsen arrived with tribute to Sui China. In 634, his son Songtsän Gampo sent tribute and a request for a heqin ("marital alliance"). In the interim, a North China aristocrat had defeated the Sui and declared himself Emperor Gaozu of Tang. When Songtsän Gampo's marriage overture arrived, Taizong, the second Tang emperor, was battling the Tuyuhun and did not initially respond, but did sent the emissary Feng Dexia (馮德遐) to Tibet to establish peaceful relations.

Meanwhile, in late 634, Taizong had sent the general Li Jing against Tuyuhun and, in a major campaign, overpowered Tuyuhun's Busabo Khan Murong Fuyun, who was killed in flight. Tang thereafter appointed Murong Fuyun's son Murong Shun as Tuyuhun's khan and, after Murong Shun was assassinated late in 635, supported Murong Shun's son Murong Nuohebo as khan.