This research report examined the relationship between the Lua ethnic group and Chiang Mai rulers as well as other ethnic groups in the Lanna region in an attempt to understand the roles and importance of the ethnic group to the region in socio-enconomic, administrative and political terms. The data were collected from evidence, legends and tales of the ethnic group residing in Hang Dong and Hot districts, Chiang Mai province, and Mae Sariang district in Mae Hong Son province. The study revealed that the Lua as commoners were obliged to respect the rulers and to accept their power. However, their relationships were rather compromising than using power of the ruling over the ruled, indicating that the former accepted the importance of the indigenous Lua. The ethnic group was granted a form of self-autonomy, called “Lap Ngern”, with an exempt from forced labor. The economic role of the ethnic group was to be farm producers, leaders in forest-product trade and other mechanisms in generating prosperity to the Lanna Kingdom.