Níngyuǎnzhōu

Ningyuan was a Yuan native prefecture on the upper Black River, in what is now Vietnam’s Lai Chau province. Founded in 1323 near Lai Chau, it belonged to Yunnan.

In 1382 the Ming placed it under Lin’an Prefecture. After the Ming withdrawal from Jiaozhi, the territory passed to Annam in 1427. Mạc ruler Mạc Đăng Dung returned part of the old prefecture to China in 1540; the Ming restored Ningyuan in 1586 but abolished it again in 1620.