Before the kingdom of Nan-chao came into being , the Thai people in Southern China evidently in more or less independent groups . They were called by their neighbors by various names, and chief among them was the Ai-Lao tribe. The present name of the Lao kingdom and people is said to have derived from this ancient word Ai-Lao. There were before the 7th century A.D., according to the Chinese , six chieftainships of the Ai-Lao people in Yunnan , and one of the southernmost of these six chieftainships , which was called by the Chinese "lok chao" or six lords , succeeded in unifying the other five chieftainships and the Thai kingdom of Nan-chao was born . There are challenges by some scholars that Nan-chao was probably a kingdom of Lolos , a tribe akin to the Tibetans who undoubtedly mixed freely with the Thai in Southern China. Here we enter into the realm of academic controversy which we had better leave forthwith .