Möng Mao

Möng Mao or Möng Mao Lông (lit.'Great Möng Mao'), also known as Maw in Burmese sources and Luchuan (麓川) in Chinese sources, was a Tai state that flourished from the 14th to 15th centuries, and consolidated dominance over the frontier regions of modern-day Myanmar, China, and India. The core territory was centered on the Nam Mao (Ruili) river basin.

Möng Mao was originally a Tai principality located on the Nam Mao (Ruili) and Longchuan regions, where it had historically managed tributary relations and political conflicts with larger states. Towards the end of the Yuan dynasty, Si Kefa became ruler of Möng Mao. During his reign, he conquered vast territories extending from Assam in Northeast India, the majority of Tai states in upper Burma, to the Red river in central Yunnan, and even marched south to destroy the kingdoms of Sagaing and Pinya.

When the Ming dynasty later entered Yunnan, Möng Mao's ruler Si Lunfa chose to submit to Ming authority and accepted imperial investiture. But shortly after, he attacked Jingdong and Moshale, which were states under Möng Mao that had defected to the Ming, leading to several wars between the two countries. At that time, the Ming government still lacked the capacity to control Yunnan's western frontier deeply and eventually accepted Möng Mao's surrender.

After Si Lunfa's death, the Ming court took the opportunity to dismantle Möng Mao, dividing its territory into numerous smaller native chieftaincies. His later successor, Si Renfa, attempted to restore Möng Mao's former domains, waging campaigns to annex neighboring tusi states. This ultimately prompted the Luchuan-Pingmian campaigns, in which the Si family was defeated and retreated to Möng Yang.

Following the weakening of Möng Mao, no single ethnic power dominated China's southwestern frontier. The various tusi regimes remained in a state of rivalry and balance, creating favorable conditions for the rise of the Toungoo Empire in Myanmar.