A number (first 12 - then 16) of these mueang, situated in the modern-day provinces of Điện Biên, Lai Châu, Sơn La as well as western parts of Lào Cai and Yên Bái grouped together and formed a long-term alliance, called Sip Song Chau Tai.

In premodern Southeast Asia's complex political geography, Sip Song Chau Tai lay at the intersection of several larger mandalas (circles of influence): At different times, it had to pay tribute to China, Vietnam, Lan Xang/Luang Phrabang (in today's Laos) and/or Siam (Thailand).

This was arranged by the French explorer and colonial representative Auguste Pavie who signed a treaty with Đèo Văn Trị, the White Tai lord of Muang Lay (Lai Châu) on 7 April 1889.

[12] In 1950, the Tai Federation was made a crown domain of the French-installed Vietnamese emperor Bảo Đại, but not an integrated part of the State of Vietnam.

Bảo Đại refrained from delegating a governor to Lai Châu, but rather left the power in the hands of Đèo Văn Long and the Tai lords.

The disempowered chief and many members of his tribe joined forces with the Viet Minh to both seek retaliation against the Đèo family and to dislodge the dominance of the White Tai.

The Geneva Agreements of July 1954 awarded the whole of North Vietnam to the communist-led Democratic Republic (DRV) and dissolved the autonomous Tai Federation, marking the end of the centuries-old rule of the feudal lords.

In order to avoid ethnic tensions, the DRV designated its northwestern provinces of Lai Châu, Sơn La and Nghĩa Lộ as the "Tai-Meo [i.e. Hmong] Autonomous Region" (Vietnamese: Khu Tự trị Thái-Mèo), modeled on the national autonomies of communist China.

It was renamed the "Northwest Autonomous Region" (Khu Tự trị Tây Bắc) in 1961, in order to not highlight just two of the many ethnic groups in this zone.