The best-known medieval Chinese name for Tibet is Tubo (; or , or , ). This name first appears in Chinese characters as in the 7th century (Li Tai) and as in the 10th century (Old Book of Tang, describing 608–609 emissaries from Tibetan King Namri Songtsen to Emperor Yang of Sui). In the Middle Chinese language spoken during that period, as reconstructed by William H. Baxter, was pronounced thu-phjon, and was pronounced thu-pjon (with the representing a shang tone).
