The 1881 Census is important in many respects. It was the first census that covered the whole length and breadth of the valley. But most importantly, it can be presumed that in 1881, the population of the valley would have been similar to that of the medieval period, and the early medieval and the early historic periods for that matter, considering the growth rate of population to be constant throughout this span of time. Someone might raise the question that beginning from the British occupation of Assam in 1836, several groups of people from the mainland India migrated to Assam, thereby changing the demographic set up in a drastic manner. But then, we have to keep in mind that Assam’s population was reduced to 2/3rd after the incessant invasions of the Burmese which continued till the British occupied the region.
What I am trying to emphasize here is that the Kacharis (including the largest group Bodos) were the most dominant population in the valley throughout its history. That they were once very influential too, can be gauged from the fact that most of the place and river names of modern Assam still continues to be that of Bodo origin. The prefix Di, meaning water in Bodo languages and dialects are invariably used in naming most of the rivers and places in Assam (e.g. Di-bru, Digboi, Disang, Dihang, Dikhou, etc). The river Brahmaputra was also earlier known as Ti-lao or Di-lao.
At present, two important divisions among the Kachari population of Assam is conspicuous, viz. the Bodos (plain Kachari) and the Dimasas (hill Kachari). There are several other groups like Hajongs, Lalung (Tiwa), Garos, Rabhas, Karbis, Morans, Chutias, etc. which are included in the greater Kachari fold. There are reasons to believe that once upon a time, such divisions among the Kacharis were not so distinguishable. Two evidences are sufficient to prove this assumption:
1. All these groups speak dialects and languages belonging to the Tibeto-Burman (TB) language sub-group of the Sino-Tibetan Family. This takes back us to a single parentage to this entire group, which probably had originated in the southern province of Sichuan in China in the prehistoric times.
2. All these Kachari population (barring the Bodos of Western Assam), until recently, used to pay an annual homage or tribute to the Kesaikhaiti Gosani Temple at Sadiya. This proves a single lineage of these various tribes, a religious knot to say more precisely.
I shall elaborate on these two points in the remaining part. The difference between the Bodos and the Dimasas is sharp at present. Traditions, however, indicates a single root to both. The Bodos call themselves Bodo-sa or Bodo-fisa (sons of the Bod country), while the Dimasas call themselves Dima-sa or Dima-fisa (sons of the great river), although they have a similar tradition of the origin of the universe, which speaks of a flood and the subsequent creation of the earth. There is another tradition among the Bodos which speaks of the existence of two groups among them, one of which happened to cross a big river because of some disputes. It seems probable that the Bodos were the ones who crossed the river and settled down on the foothills of the Himalayas and later were disowned by the Dimasas, who initially settled on the foothills of the Patkai and the Naga Hills and the Dhansiri and Kopili valleys. In all likelihood, they entered the Brahmaputra valley through the Patkai Hill Range. When did it happen?
This is, perhaps, the most intriguing issue which I can see, will dominate the archaeological and anthropological studies in Assam for the coming decades. I shall just try to present the recent trends in both these disciplines to come out with a solution.
Renowned linguist George Van Driem, a professor in the Leiden University in the Netherlands suggested that a western group of the Proto Tibeto-Burmans branched out from the original homeland, i.e., the Sichuan Province of Southern China (Archaeology and Language II 1998). Looking at the corresponding archaeological evidences, he confined a date between 6000-2000 BC for this supposed migration. He preferred to state that there were several waves of migrations. But recent genetic studies on the TB people of the Northeast India and those of Eastern Asia and Southeast Asia has proved that the TB of Northeast India spread out into the region from a single stock. The Y-chromosome of the Northeast India tribes, which corresponds to a male lineage shares a lot of characteristics with the East Asian TBs, and also shows a genetic bottlenecks. This proves the fact that, the TBs migrated from East Asia in a small number to the Brahmaputra valley and dispersed in subsequent times. Another explanation regarding the date of the arrival of these people can also be made from such studies: the Northeast Indian TBs got separated from the parent group at an earlier date. Another group migrated to Southeast Asia more or less at the same time.
Archaeological records, however, conflict this view to some extent. The Neolithic implements of Bangladesh, Tripura, and also North Kachar Hills and Manipur share interesting characteristics, especially the raw material (fossil wood) and the technique of manufacturing. Could this have been a different belt of Neolithic culture, separate from the Neolithic of the other regions of the Brahmaputra valley, and having affinities with the South East Asian Neolithic? Could there have been a different migration of the Tibeto-Burmans from South East Asia? These are questions to be answered on the basis of farther research. But one thing seems clear that the Kacharis, who were the forbearers of the Neolithic culture of the Brahmaputra valley entered through the Sadiya region at an early date, may be around or before 2000 BC, although no sequential or absolute dating is available to confirm this view at present.
The greatest contribution of the Neolithic TBs to Assam is the introduction of rice cultivation. Manjil Hazarika (Ancient Asia, Vol.1. 2006) has highlighted this point in a recent article. Archaeological remains of rice cultivation are, however, difficult to find in Assam. But I have a strong feeling that the foothill regions of the Himalayas bordering Arunachal Pradesh and also Naga Hills will provide definite evidence of early rice cultivation in Assam and thus will help in establishing a cultural sequence. The distribution of the Kacharis (TB) within the valley happened hand in hand with the spread of this Neolithic tradition.
In regard to the medieval kingdom of the Kacharis, situation is not far too good to get conclusive results. When I see the enormous remains of the brick-built fortified towns of the Dhansiri valley, the brick monuments of Sadiya, the tanks and pottery of the Kopili valley, I am left without the slightest doubt that they are the extant remains of the early medieval and medieval kingdoms of the Chutias and the Kacharis. The brick size and texture is remarkably similar, or rather I would prefer to say, they are typically Kachari bricks. It is wonderful to see that the Kacharis developed the art of burnt brick-making as early as the 7-8th CAC, while the Ahoms could never master this art till the 17th century, when Rangpur was built. All the Ahom ramparts and forts were totally devoid of bricks! Brick-making is definitely another significant contribution of the Kacharis to the Heritage of Assam.
The makers of the medieval kindom of Sadiya were definitely the Chutias and those of the Dhansiri valley were Dimasas, which can be put beyond any doubt. The Chutias, later on, got amalgamated to the greater Assamese society, while the Dimasas fled from the Dhansiri valley following their defeat at the hands of the Ahoms in 1536, and dispersed in the North Kachar Hills. They formed a petty kingdom initially at Maibong and later shifted to Khaspur. A detailed history of this kingdom can be found (Kachari Buranji, S.K. Bhuya). But the most of this compact Dimasa people got dispersed and became isolated after their retreat from Dhansiri valley. One such group of Dimasas was noticed even in Nagaland by K.S. Singh (Scheduled Tribes, People of India Series 1994). We do not have concrete evidence for the earliest date of these Kachari kingdoms. But it might have started after the degeneration of the Kamarupa Kingdom, around 10-11th CAC. But that the Kacharis were even dominant during and before the Kamarupa regime can be put beyond doubt. Such a situation in the early history of Assam helped in assimilation to a great extent which later on became the greater Assamese identity.
There were several other petty kingdoms or rather principalities of various Kachari groups (e.g. Dimarua, Beltola, etc.) in the middle and lower Assam regions which continued to exist independently until recent times. Archaeological remains are also found. As for the Bodos of the northern bank of the Brahmaputra, it is however, difficult to say whether they formed a dynasty of their own. They remained in relative isolation for most part of the history, although practically remaining within the Kamarupa regime during the early historic and Kamata kingdom during the medieval periods. The Koch kingdom of Koch Behar can also be attributed to the greater Bodo family (the Koches were Hinduised Bodos with admixture with the Indo-Europeans).