On the east the Kachin, Shan and Karen hills, extending from the valley of the Irrawaddy into China far beyond the Salween gorge, form a continuous barrier and boundary, and tail off into a narrow range which forms the eastern watershed of the Salween and separates Tenasserim from Siam.
The northern portion of the Karen hills is at present dealt with on the principle of political as distinguished from administrative control.
Farther north the country is peopled by Laos, scattered in villages along all the river banks, and by numerous communities of Shan, Karen, Kamoo and other tribes living in the uplands and on the hilltops.
Of this total about 3,000,000 are Siamese, about 2,000,000 Laos, about 400,000 Chinese, 115,000 Malay, 80,000 Cambodian and the rest Burmese, Indian, Mohn, Karen, Annamite, Kache, Lawa and others.
The Red Karen women weave their own and their husbands' clothing.