The Lepcha (also called the Rong) are the aboriginal inhabitants of Sikkum, India. There are about 46,000 Lepcha people. They are thought to be the earliest inhabitants of Sikkum. Traditionally, the Lepcha are hunters and gatherers, but now show signs of farming and cattle breeding. They were described in some British sources as forest dwellers. The Lepcha people usually live in the most remote valleys. They isolate themselves from other Indian societies and they speak their own language, which is a sub-dialect of Tibetan. They are monogamous, although there have been cases when a man may have more than one wife.
The Bhutia converted the Lepcha people to Tibetan Buddhism. The Lepcha still retain their beliefs of spirits and shaman, who communicate with the gods, cure disease, and watch over the ceremonies of birth, marriage, and death.
References:
"Lepcha" International Institute for Asian Studies: Himalayan Language Project. http://iias.leidenuniv.nl/host/himalaya/individ/lepcha.html
"Lepcha" Britannica.com. http://www.britannica.com/eb/article-9047855