Hso

The Hso ruled Möng Mao, a great Tai Shan state in the Ruili river valley on the Yunnan-Myanmar frontier. Their Shan prefix Hso was written by the Chinese as the surname Si. Hso Hkan Hpa, called Si Kefa (1294-1369), seized power about 1335 and united neighbouring Tai states.

Four Yuan expeditions against him between 1342 and 1348 failed; in 1355 he accepted the Yuan title of Pingmian Pacification Commissioner. His armies extracted tribute from Assam and in 1364 sacked Sagaing and Pinya, clearing the way for Ava.

Si Lunfa was invested by the Ming after 1382 but repeatedly fought them; after his death they partitioned the kingdom into five tusi. A later ruler, Si Renfa, tried to rebuild the old domains from 1413, provoking the Luchuan-Pingmian campaigns of 1436 to 1449, in which the house was defeated and driven back to Möng Yang.