Chronicle of Sipsong PannaThe Tai L are a Tai speaking group closely related to the Khon Mang or Tai Yuan, the dominant ethnic group in Northern Thailand. According to their own historical tradition, the ancestors of the Tai L migrated from what is now northwestern Vietnam into the southern part of Yunnan, where they founded their own kingdom in the twelfth century. Today, the Tai L are the most important population group within the so called "Economic Quadrangle" of the Upper