Many ethnic groups have several sub-groups and sometimes costume, language and traditions can change from one village to another.
Broadly speaking, the myriad ethnicities fall into 3 ethno-linguistic categories: Tai/Kadai including Shan and other Tai minorities such as Tai Leu; Mon/Khmer peoples which includes Wa, Palaung, Loi and Enn; and Sino-Tibetan groups such as Lisu, Lahu, Akha and Akhu.
The Mon Khmer groups are the oldest inhabitants currently populating this region and have certainly been around for at least a couple of millennia. As the name suggests they are related to the Mon of southern Burma and the Khmer of eastern Thailand and Cambodia who inhabited much of mainland Southeast Asia before the arrival of Tai, Burmo-Tibetan and Vietnamese migrants from Southern China. Tai groups began migrating into northern Vietnam, Laos, Thailand and what is now Shan State during the 13th century, pushing the indigenous Mon Khmer groups into the hills. The Sino-Tibetan peoples, as in Laos and northern Thailand, are more recent arrivals from northern Yunnan/Eastern Tibet.
Today Shan form the overwhelming majority in the region, though smaller Tai groups such as the Tai Leu can be found closer to the Lao border. These are eastern Shan and their language is much closer to modern (Siamese) Thai than say inhabitants of Taunggyi or Lashio and any visitor speaking a smattering of Thai will have no problem making themselves understood. Neither Shan women nor men wear traditional costumes except for special occasions, though many of the outlying villages still have very traditional houses and lifestyles. Neither are they particularly fond of Burmese 'affectations' such as longyiis or thanaka.
The various Mon Khmer groups have similar though not identical languages but widely varying costumes and include animist, Christian and Buddhist villages. (A visitor from Phnom Penh for example wouldn't be able to do more than catch the occasional word but the languages do have the same origins.) Wa usually live slightly further north than Kengtung so the villages found in this region are mostly settled by refugees – fleeing both conflict with the Burmese government or the Shan or simply conscription into the United Wa State Army and/or participation in the drugs trade. You may still see some traditional-style mud houses in Wa villages but few traditional costumes. Not so the Palaung however, whose women sport spectacular outfits in everyday life and particularly for showing off in Kengtung market. Palaung are found in a wide swathe across Shan State though in the Kengtung region they are predominantly Red Palaung and wear an identikit red and black costume with highly elaborate waistbands.
The Enn are a small ethnic group inhabiting only this region and are known locally in vulgar fashion as the 'Black Tooth Tribe' due to their penchant, even at an early age, for betel. Spectacularly dressed Enn can be seen in the market too and the younger men of the tribe like to 'dress up' to go into town. Loi are generally similarly clad to local Shan though can be identified by their turbans. You'll see many Loi working in Kengtung market.
Most of the Sino-Tibetan groups will be familiar to tourists who've already visited northern Thailand or Laos though subgroups of Akha, Lisu and Lahu may vary. The Akhu -- closely related but with differing costumes and traditions to the Akha – are also rarely encountered outside of Kengtung district. Again some villages may be Christian (Baptist, Protestant or Catholic!), while others Buddhist and remoter ones still animist. As with the Palaung some of these peoples have been relocated to more accessible valley areas to reduce their former tendency to grown opium and so the villages closer to roads and Shan settlements have lost some of their traditional characteristics.
By Mark Ord.
The Travelfish newsletter is sent out every Monday and is jammed full of free advice for travel in Southeast Asia. You can see past issues here.