Shǔ

Shu, or Ba-Shu Chinese, was the Chinese speech of the Sichuan Basin from the Han dynasty to the Mongol conquest. It was noted as a distinct regional language in the Fangyan, compiled in the Western Han.

One of the earliest branches to split from Old Chinese, it diverged even earlier than Min and, like it, did not descend from Middle Chinese. In 1236 the Mongols sacked Chengdu, and by the final Song defeat of 1279 the basin had been depopulated and the old language's transmission was broken.

Under the Ming and Qing dynasties, settlers from Huguang and other provinces brought the speech that developed into Southwestern Mandarin. Ancient Shu died out, although the Minjiang dialects of southern Sichuan kept part of its vocabulary and phonology.