Wikipedia
Theinni or Hsenwi (; , ; , , ) is a town in northern Shan State of Burma, situated near the north bank of the Nam Tu River and now the centre of Hsenwi Township in Lashio District. It is 28 miles north of Lashio. It is 2,100 feet above sea level.
After the disruption of the ancient Shan empire at Tali by Kublai Khan, Theinni seems to have been the centre of the independent Shan kingdom, with various capitals in the Shweli River and Nam Tu River valleys. This kingdom of Kawsampi was ended by the Burmese about 1738, and the country was divided into various states, with appointment orders from Ava. Numerous rebellions and civil wars reduced Theinni from its position as the most powerful and populous Shan state to a condition of fearful desolation. It later regained much population since the British occupation in 1888, but is still far from its old prosperity. The ruins of what was the old capital of Hsenwi State lie at a short distance, and show it to have been a large and well-built town.