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The Limbu:
The Yakthung or Limbu tribes and clans belong to the Kirati nation or to the Kirat confederation. They are indigenous to the hill and mountainous regions of east Nepal between the Arun and Mechi rivers to as far as Southern Tibet, Bhutan and Sikkim.

The name Limbu is an exonym of an uncertain origin. The word Limbu roughly translates as an archer or 'the bearer of bows and arrows'. They call themselves Yakthumba/Yakthung (in Limbu language). They are also known as Shong, Xong or Drenjongka དརེན་འཛང་ཀ་ (in Tibet) or Chong, Tsong འསང་ in (Sikkim). Their estimated population of 700,000 is centered in the districts of Sankhuwasabha, Tehrathum, Dhankuta, Taplejung, Morang, Sunsari, Jhapa, Panchthar and Ilam in Nepal. These districts are all within the Mechi and Kosi zones also known as Limbuwan. Portions of the Limbu population are also located in the East and West districts of Sikkim. A smaller number are scattered throughout the cities of Darjeeling and Kalimpong in West Bengal, India, and in North and South Sikkim and Bhutan.

Limbu Clans and Tribes are divided into the Lhasa gotra (from Lhasa, Tibet) and Yunan gotra (from Yunan, China). The Limbu are known as Yakthung Thi-bon or Des Limbu (ten Limbu), from which thirteen Limbu sub-groups have emerged. According to legend, five of the groups came from Yunan, China and the other eight from Lhasa, Tibet.Unlike the caste system which was brought to the Nepal region after the Hindu invasion, a caste system is not practised among the Limbu people and Limbu sub-groups. However, there are numerous different clans and family-sects.

Language:
Limbu (Limbu:Yakthungpan; "Language of the Yakthung") is a Sino-Tibetan/Tibeto-Burman language spoken in Nepal, Sikkim, Kashmir and parts of Northern India by the Limbu and Monpa community.

Limbu language went through its own unique evolution from the Tibetan and Devanagiri writing systems. Far more Limbus are literate in Nepali than in Limbu, thus many Limbu publications are accompanied by Nepali translation.Limbu language is one of the major spoken and written languages of Nepal, Sikkim, and other parts of Northern India. Today, linguists have reached the conclusion that pronominalization is an indigenous development of the Tibeto-Burman language, and Limbu language bears a close resemblance with Khambu Sampang and other unique Tibetan dialects. Limbu language has four main dialects: Panchthare, Tamarkhole, Phedape and Chatthare. Before the introduction of Sirijonga script among Limbu Kiratas, Rong script was popular in East Nepal, especially in the early Maurong state. Sirijonga script nearly disappeared for 800 years, but it was brought back into practice by Te-Ongsi Sirijonga Thebe of Tellok Sinam.

Economy:
The Limbus traditionally practiced subsistence farming. Rice and maize comprised their principal crops. Although there is an abundance of arable land, productivity is greatly limited by insufficient technology. Excess crops are often traded for food that cannot be grown in the region.

A sizable number of Limbu youths are enlisted in the British and Indian Gurkha regiments, providing their families with a steady stream of income. This income from military service helped to improve the Limbu community as a whole in terms of health and education.