Before the twentieth century the inland states of South east Asia formed a network of principalities situated in upland valleys where the inhabitants were wetland rice farmers The major outside influence was Theravada Buddhism that assimilated, or in some cases was grafted onto the practices of ancient indigenous spirit religion In the surrounding hills, the people, control by their own rulers, practised swidden agriculture and animism. The rulers of the uplands and the valleys claimed hereditary rights through mythical kinship links to the highes guardian spirits This inland culture was distinctive from that of coastal Southeast Asia, but was as rich and as complex was based on a relatively egalitarian ideology that permitted the flowering of indigenous skills and innovations, especially among women, and a complex history that involved conquest and migration