[6] A Minyak prince called Khye Bumsa (Wylie: Gyad 'bum bsags) is said to have settled in Chumbi and established a small kingdom.

The ruins of the house built by Khye Bumsa were reportedly present in the Chumbi village till the end of the 19th century.

A Lepcha chieftain called Gaeboo Achyok (Gyalpo Ajok, r. c. 1660 – 1676) based at Damsang (in the present day Kalimpong district) faced invasions from the Bhutanese and obtained Dalai Lama's assistance.

The end result of these conflicts is not clearly documented, but the Bhutanese were evicted from the lower Chumbi Valley and its control passed to the Sikkimese and Tibetans in some form.

About 2 miles (3.2 km) upstream from Chumbi lies the town of Yatung (Shasima), the present headquarters of the Yadong County.