There is undoubtedly a dominance of the Mongoloid element in the population of North-East India. Besides the racial differences, there is a tribal–nontribal duality recognized by the Constitution of India to secure certain benefits to the tribal community, to enable them to catch up with the rest of the society in educational attainment and the level of living. Most of the tribes or tribal communities are concentrated in the hilly states of Arunachal Pradesh; Nagaland; Manipur; Mizoram, on the Myanmar border; and Meghalaya, sandwiched between Assam and Bangladesh.

People of Northeast India
Northeast India has over 220 ethnic groups and an equal number of dialects, with Bodo being the largest indigenous ethnic group. In the north-eastern states of Arunachal Pradesh, Meghalaya, Mizoram, and Nagaland, upward of 90 percent of the population is tribal. However, in the remaining northeast states of Assam, Manipur, Sikkim, and Tripura, tribal peoples form between 20 and 30 percent of the population.
People of Assam
Human settlement in the region probably dated back 2000 B. C. since when, it is known with certainty that, there was a movement of population from the Hwangho and the Yang-Tse-Kiang in China to India through Assam and these Mongolid people along with others who migrated from Northern Burma (Myanmar) formed the bulk of the population of Assam.
Later, there was a wave of migrations into Assam through the northeastern routes. These migrants belong to the 'Indo-Chinese linguistic family, ' of which the two most important subfamilies are Mon-Khmer and the Tibeto-Burman. The third, Siamese-Chinese, includes Sban, which was spoken by the Ahoms, the last of these invaders.
Out of these three Mongolian groups, Assam has at present descendants of the last two known as the Boro, Kacharis and Ahoms respectively. A group of Aryans had made their eastward move, entered Assam through Bihar and North Bengal, and had spread their culture and civilization in the western part of Assam. It is claimed by some scholars that a group of Aryans penetrated far east of Assam and established cities and kingdoms as early as the Mahabharata period. In the process of these two immigrations, a significant fact of Aryan and Mongolian traits leading to the present Assamese culture.
Assam is acknowledged as the settling land for a lot of
cultures.
Ahoms, along with Chutia, Moran, Motok, and Koch, are still regarded as semi-tribal groups who have nominally converted to Ekasarana Dharma even though keeping alive their own tribal traditions and customs.
As per the latest development, indigenous ethnicities like Moran, Chutia, Motok, Tai Ahoms, and Koch & also non-indigenous ethnic groups like the Tea tribes have realized the above-mentioned points and have applied for ST status. This will make Assam a predominantly tribal state having wider geopolitical ramifications.
People of Arunachal Pradesh
The ancient history of Arunachal Pradesh remains uncertain, yet many traces can be made to Indian History. It is often believed that Arunachal has an ancient connection with India and its mention can be found in the Mahabharata and the Kalika Purana. Sage Parshurama had washed off his sins in the Lohit District, Maharshi Vyasa had meditated here and Lord Krishna is said to have married Rukmini here. The sixth Dalai Lama was born here in Tawang in the 17th century. This rich and diverse backdrop makes Arunachal Pradesh one of the significant parts of India’s unique history.
The state is inhabited by the world’s largest variety of ethnic tribal groups and subgroups, numbering over a hundred, and each tribe speaking their own language and dialect. Their diverse and unique rich culture and traditional heritage constitute arts and crafts, festivals, social structure, and folklore in the form of songs and dances that still remain fresh and well-preserved in this state.
A place brimming with tremendous anthropological richness, Arunachal Pradesh is home to several groups of indigenous people. Broadly speaking, there are three cultural groups; first being Monpas and Sherdukpen of Tawang and West Kameng districts who are followers of the tradition of Mahayana Buddhism. The second group comprises Apatanis, Adis, Galos, Mishmis, Nyishis, Tagins, Akas etc worship the Sun and Moon God while the third group, including Noctes, Wanchos and Khampti (tribal communities of TLCN – Tirap, Longding, Changlang, Namsai) follow basic Vaishnavism and Buddhism respectively and are ruled by a hereditary chief. Additionally, there are the Galo, Nyishi, Tagin, Apatani and Adi communities who are commonly known as Tani clans due to their connection with Abotani (abu/abo-father, tani-tribes) – from whom the mythical heritage of mankind’s origin is associated.
People of Manipur
People of Manipur include Meitei, Naga, Kuki, Meitei Pangal and other colorful communities which have lived together in complete harmony for centuries. These are the people whose folklore, myths & legends, dances, indigenous games and martial arts, exotic handlooms & handicrafts are infused with the mystique of nature. The wonders have no end in Manipur.
About two-thirds of the people are Meitei (Meetei), who occupy the Manipur valley and are largely Hindus. Meitei women conduct most of the trade in the valley and enjoy high social status. Indigenous hill tribes, such as the Nagas in the north and the Kukis in the south, make up the rest of the population. Divided into numerous clans and sections, the people of these tribes speak languages of the Tibeto-Burman family and practice traditional animist religions. Some of the Nagas have been converted to Christianity. More than three-fifths of the people speak Manipuri, which, along with English, is the official language of the state. Manipur’s population is largely rural, Imphal being the only city of any size.
People of Meghalaya
Historical accounts suggest that there were waves of migration into Northeast India through the north-eastern routes and these migration were rather invaders who belong to the "Indo-Chinese Linguistic Family" of which two most important sub-families are the Mon-Khmer and Tibeto-Burman. The Mon-Khmer, which constitutes the Khasi and the Jaintias, was driven by subsequent Tibeto-Burman hordes into the Khasi Hills, where that sub-family now exists.
The Tibeto-Burman sub-family had three groups, viz., Naga, Kuki-Chin and Bodo. The Naga and the Kuki were driven to the hills in the northeast and the Bodo dominated in the plains, Garo Hills and the North Cachar Hills. The Bodo were later divided into several small linguistic groups such as Garo, Kachari, Mech, Dimasa, Tippea, Lalung, Rabga and Chutia.
People of Mizoram
Historian believes that the Mizos are a part of the great wave of the Mongolian race spilling over into eastern and southern India centuries ago. Their sojourn in Western Burma, into which they eventually came around the seventh century, is estimated to have lasted about two centuries. They came under the influence of the British Missionaries in the 9th century, and now most of the Mizos are Christians. One of the beneficial results of Missionary activities was the spread of education.
The Missionaries introduced the Roman script for the Mizo language and formal education. The cumulative result is a high percentage of 95 % (as per the National Sample Survey 1997-98), which is considered to be the highest in India. The Mizo area's distinct community and social unit was the village. Around it revolved the life of a Mizo. Mizo Village is usually set on the top of a hill, with the chief's house at the center and the bachelor’s dormitory called Zawlbuk prominently. In a way, the focal point in the village was the Zawlbuk, where all young bachelors of the village slept. Zawlbuk was the training ground, and indeed, the cradle wherein the Mizo youth was shaped into a responsible adult member of the society.
The residents of Mizoram consist almost entirely of Scheduled Tribes (an official category embracing indigenous groups that fall outside the predominant Indian social hierarchy). These groups are loosely called Mizo, a local term meaning “highlanders.” Among the most prominent of the Mizo peoples are the Kuki, Pawi, and Lakher. Most of the Mizo are Tibeto-Burman peoples, speaking Mizo or a closely related Tibeto-Burman language or dialect. One group in the state, however, the Chakma, speaks an Indo-Aryan language. Mizo and English are the principal and official languages. Having no script of its own, Mizo uses the Roman alphabet.
People of Nagaland
The derivation of the word 'NAGA' used for the people of this land is obscure. It has been generally believed that the term Naga is derived from Kachari 'Naga ', meaning young man and hence warriors the source of this word. Verrier Elwin thinks that the word is derived from 'Nok' meaning people in a few Tibeto-Burman languages.
Nagaland has a rich linguistic tradition with as many languages as there are tribes, each exclusive to itself. What is even more remarkable is that even within the language of a particular tribe, there are dialects mutually unintelligible. For instance, in some tribes like the Angami, every village has a slightly different variation even within the same dialect-this variance progressively increasing with the geographical distance. This makes inter-tribe and intra-tribe communication very difficult. In the circumstances, English has come to serve as the State language while Nagamese, a kind of pidgin Assamese, has become the common lingua franca.
The Nagas, an Indo-Asiatic people, form more than 20 tribes, as well as numerous subtribes, and each one has a specific geographic distribution. Though they share many cultural traits, the tribes have maintained a high degree of isolation and lack cohesion as a single people. The Konyaks are the largest tribe, followed by the Aos, Tangkhuls, Semas, and Angamis. Other tribes include the Lothas, Sangtams, Phoms, Changs, Khiemnungams, Yimchungres, Zeliangs, Chakhesangs (Chokri), and Rengmas.
People of Sikkim
Roughly three-fourths of Sikkim’s residents are Nepalese in origin; most speak a Nepali (Gorkhali) dialect and are Hindu in religion and culture. About one-fifth of the population consists of Scheduled Tribes (an official category embracing indigenous peoples who fall outside the predominant Indian social hierarchy). The most prominent of these tribal groups are the Bhutia, the Lepcha, and the Limbu; they all speak Tibeto-Burman languages and practice Mahayana Buddhism as well as the indigenous Bon religion.
The Lepchas
The original inhabitants of Sikkim are said to be Lepchas.
They existed much before the Bhutias and Nepalese migrated to the state. Before
adopting Buddhism or Christianity as their religion, the earliest Lepcha
settlers were believers in the bone faith or mune faith. This faith was
basically based on spirits, good and bad. They worshipped spirits of mountains,
rivers and forests, which was natural for a tribe that co-existed so
harmoniously with the rich natural surroundings. The Lepcha (Zongu) folklore is
rich with stories. The Lepcha population is concentrated in the central part of Sikkim. This is the area that encompasses the confluence of the Lachen and
Lachung rivers and the Dickchu.
The Bhutias
These are the people of Tibetan origin. They migrated to
Sikkim perhaps somewhere after the fifteenth century through the state of
Sikkim. In Northern Sikkim, where they are the major inhabitants, they are known
as the Lachenpas and Lachungpas. The language spoken by the Bhutias is
Sikkimese. Bhutia villages are as large as those compared to those of the Lepchas.
A Bhutia house called “Khin” is usually of rectangular shape.
The Nepalese
The Nepalese appeared on the Sikkim scene much after the Lepchas & Bhutias. They migrated in large numbers and soon became the dominant community. The Nepalese now constitute more than 80% of the total population. The Nepali settlers introduced the terraced system of cultivation. Cardamom was an important cash crop introduced by the Nepalis. Except for the Sherpas & Tamangs, who are Buddhists, the Nepalis are orthodox Hindus with the usual caste system.
People of Tripura
The original tribes of Tripura are the Tripuri, who used to be
known as "PANCHA TRIPURA," that is five Tripuris, during the Manikya
Monarchy, till its merger with the Indian Union. The five branches are Tripuri/Tripur, Tripura,
Jamatia, Reang, and Halam. Within these five main branches of Tripuris, there are
smaller sub-branches like Murasing, Uchui, Rupini, and Kolois, etc. These
branches have many sub-branches that have their own little
characteristics.
The people of Tripura are said to belong to the same origin as the Katcharis; the similarities in their religion, customs and appearance make this probable. It may be added that the Rajas of both countries, Tipperah and Katchar.
The Tripuri constitute more than half the tribal community.
Other prominent tribal groups include the Reang, the Chakma, the Halam (a
subgroup of the Kuki), the Garo, the Lusai (Mizo), and the Marma (Mogh); most
originally moved to Tripura from various hill regions in neighboring states.
Bengali (Bangla), an Indo-Aryan language, is spoken by more
than half the population; it and Kokborok (Tripuri), a Tibeto-Burman language,
are the state’s official languages. Manipuri, another Tibeto-Burman language, is also widely spoken.
Hinduism is the religion of the great majority of Tripura’s people. Muslims constitute the largest minority but account for less than one-tenth of the population. There are also small minorities of Christians, particularly among the tribal peoples. Most of the Chakma and Mogh are Buddhist.