The Koch dynasty (; 1515–1949) ruled parts of eastern Indian subcontinent in present-day Assam and Bengal. Biswa Singha established power in the erstwhile Kamata Kingdom which had emerged from the decaying Kamarupa Kingdom."Kamarupa was reorganized as a new state. 'Kamata' by name with Kamatapur as capital. The exact time when the change was made is uncertain. But possibly it had been made by Sandhya (c1250-1270) as a safeguard against mounting dangers from the east and the west. Its control on the eastern regions beyond the Manah (Manas river) was lax." The dynasty came to power by overthrowing the Baro-Bhuyans of the region, who had previously ended the brief rule established by Alauddin Hussain Shah.
The dynasty split into three among the descendants of Biswa Singha's three sons: two antagonistic branches Koch Bihar and Koch Hajo and a third branch at Khaspur. Koch Bihar aligned with the Mughals and the Koch Hajo branch broke up into various sub-branches under the Ahom kingdom. Koch Bihar became a princely state during British rule and was absorbed after Indian independence. The third branch at Khaspur (Khaspur kingdom) was absorbed completely into the Kachari kingdom. Raikat is a collateral branch of the Koch dynasty that claim descent from the Sisya Singha, the brother of Biswa Singha.
Etymology The name Koch denotes a matrilineal ethnic group to which Biswa Singha's mother belonged;"(I)t becomes clear that Biswa Singha's father was a Mech and mother was a Koch and both the tribes were "rude" and "impure", hence non-Aryan or non-Hinduised." and the king as well as most of the population of the kingdom (Kamata Kingdom) belonged to the Koch community. The Koches were of Dravidian-Mongoloid origin. "The dynasty was Koch and the name of kingdom was Kamata (Koch) because the king himself and most of the population belonged to the Koch community"
History Historical background
After the fall of the Pala dynasty, a Bengali dynasty from Varendra, the kingdom fractured into different domains in the 12th century. Sandhya, a ruler of Kamarupanagara (present-day North Guwahati) moved his capital further west to present-day North Bengal in the middle of the 13th century and the domain he ruled over came to be called Kamata kingdom. The buffer region, between the eastern kingdoms and Kamata was the domain of the Baro-Bhuyans chieftains. Alauddin Husain Shah of Gaur removed Nilambar of the Khen dynasty in 1498, occupied Kamata and placed his son Danyal Husayn in charge. Within a few years the Baro-Bhuyans—led by one Harup Narayan of the Brahmaputra valley—defeated, captured, and executed Daniyal, and the region lapsed into Bhuyan confederate rule.
Emergence of the Koch power It was in this context that a number of independent Koch tribes were united under a leader named Hajo, who occupied Rangpur and Kamrup."The Koches 'who had a number of chiefs, at first independent, but who gradually united under the authority of one of themselves named Hajo, occupied Rangpur and Kamrup" The Koches, spreading towards the southern plains, were able to ally with other tribal groups."Having moved from the Himalayan terrain, probably following the courses of the Teesta and Dharla rivers, the Koches settled first in North Bengal and then spread gradually towards the east, south and west, thereby allying with other tribal groups like the Rabhas, Dhimals, Hajongs, Garos, and Meches (Nath 1989: 1-4)." Among various factors, the shift from slash-and-burn cultivation to settled cultivation and the breakdown of tribal clan-based relations are given as factors that contributed to the growth of Koch power." (I)t is clear that the centre of Koch power was gradually moving towards the southern plains of the region. This repeated transfer of capital was associated with a shift in their subsistence from jhum cultivation to settled agriculture (Ray 2002: 48). Simultaneously, there was a change in their political system from a clan-based chiefdom to a state with multiple agents involved in its functioning. Both the processes are commonly observed among rising local powers with indigenous origin in the northeast between the fourteenth and eighteenth centuries (Shin 2020: 49-75)."
As part of these alliances Hajo's daughter Hira married Hariya Mandal, a member of the Mech tribe from Chiknagram in present-day Kokrajhar district,"[Hajo] had two daughters, Hira and Jira of whom Hira was married to Hariya, a member of the "impure tribe" called Mech." though these ethnic identities are difficult to discern since there were frequent intermarriages."Subject to differences of opinion, the progenitor of the Koch monarch was either a Koch or a Mech, Haria Mandal by name..." "Frequent intermarriage between the Koches and the Meches made them come close to each other, thereby making differentiation between the two groups difficult in both the historical and fictional narratives. The founder of Koch political power was Visva Sinha (1515-40), the son of Haria Mandal who was the head of twelve leading Mech families and inhabited Chiknabari in Mount Chikna near Bhutan hills." Bisu, born to Hariya and Hira,"[Hajo] had two daughters, Hira and Jira of whom Hira was married to Hariya, a member of the "impure tribe" called Mech. Of them was born Bisu...it becomes clear that Biswa Singha's father was a Mech and mother was a Koch and both the tribes were "rude" and "impure", hence non-Aryan or non-Hinduised." acquired the political legacy of his grandfather Hajo and established himself as the chief of the eastern branch of the Koches in the Khuntaghat region (present-day Kokrajhar district of Assam). It is thought that Bisu fought under the leadership of the Bhuyans as a landlord against the occupation of Kamata kingdom by Alauddin Husain Shah and thus learned their military tactics."Bisu, who might have fought Alauddin Hussain Shah or his government in Kamrup under the leadership of the Bhuyans and had a knowledge of their (the Bhuyans') military tactics..."
Consolidation of power under Bisu He sought the alliance of tribal chiefs,"Visva placed considerable dependence on tribal force in warfare. Tribal militia, consisting of the Meches, Koches, Kacharis, Bhutias and so forth, continued to participate in aggressive warfare under Naranarayan, resulting in a great expansion of the Koch territory (Barman 2007: 83-87)""...Dimarua, Panbari, Beltola, Rani, Moirapur, Borduar, Bholagram, Pantanduar, Chaigaon, Bogaduar, Bongaon, Baku, Luki, Hengerabari. Biswa Singha received the allegiance of these states including those of Darrang, Karaibari, Atiabari, Kamtabari, and Balrampur. The ruling family of these states till the annexation of the lower Brahmaputra valley to the British in 1826 were Koch, Mech or Garo and some of them claimed the continuity of their rule since centuries back" against the more powerful Baro-Bhuyans and began his campaign around 1509. Successively, he defeated the Bhuyans of Ouguri, Jhargaon, Karnapur, Phulaguri, Bijni and Pandunath (Pandu, in Guwahati)."It is stated that Biswa Singha subjugated the Bar Bhuyan then the Saru Bhuyan and then the Bhuyan of Ouguri. After this he defeated the Daivajnya Chuti Bhuyan and thereafter Kusum Bhuyan, Dihala Bhuyan, Kalia Bhuyan and the Bhuyans of Jhargaon, Kabilash Bhuyan, the Bhuyans of Karnapur, Phulaguri, and Bijni, and finally Pratap Rai Bhuyan of Pandunath, Guwahati. The Gurucaritas also mention Gandhanva Rai, the Bhuyan of Banduka and Sriram Khan of Sajalagram." He was particularly stretched by the Bhuyan of Karnapur, and could defeat him only by a stratagem during Bihu.
In some records Bisu moved his capital from Chikana to Hingulabas (near present-day Samuktala) and then finally to Kamatapur (now called Gosanimari) which is just a few miles southeast of the present-day Cooch Behar town"With his military and administrative ability, Viva crushed a number of Bhuyans, local chiefs with a huge estate and military strength, subjugated other hilly areas and set up a new polity about 1515. He shifted the political centre from Chikanbari, his native village close to Bhutan border, to Hingulabas, a village in the plains of western Duras, and then finally to Kamatapur, the fortified city occupied by the Khens about a century earlier"—but since these movements were recorded much after the events the dates and rulers associated with these movements are not expected to be accurate and these movements represent the gradual movement of Koch power towards the southern plains of the Brahmaputra Valley."Since the sources are of a much later date than the events they record, the date of occurrence and the kings credited with each shift of the capital may not be accurate. But, as Ray points out, it is clear that the centre of Koch power was gradually moving towards the southern plains of the region." After subjugating the petty rulers, he announced himself the king of Kamata bounded on the east by Barnadi River and on the west by the Karatoya River in the year 1515.
The Koch dynasty in Kamata was one of several tribal formations that developed into statehoods around 15th century in northeast India—Ahom, Chutia, Dimasa, Tripura, Manipur, etc.
Sanskritisation At his coronation Bisu adopted Hinduism and the name Biswa Singha."(Bisu) adopted Hinduism and assumed the name Biswa Singha after his coronation (Barpujari 2007: 69–71; Gait 2008: 49–50)." Nevertheless, he retained the Koch identity of his mother discarding the ethnic identity of his father."It is interesting to note that Bisu, the founder of the dynasty and son of Haria Mandal, a chieftain of the Tibeto–Burman origin, discarded the tribal affinity of his father, but retained Koch identity of his mother (Bisu’s mother, Hira belonged to the Koch origin) adopted Hinduism and assumed the name Biswa Singha after his coronation (Barpujari 2007: 69–71; Gait 2008: 49–50)." Later, Brahman pundits created a legend that lord Siva was the father of Biswa Singha to give legitimacy to his rule"It is common to believe Biswa Singha's origin as son of Siva was nothing but creation of the Brahmans..The Brahmans needed royal patronage and the king wanted legitimacy which could be obtained through the universal religion to teach the people to be obedient, patient and submissive" and conferred on him the status of the Kshatriya varna. According to the legend constructed at the time of coronation, Bisu was son of Siva and his tribe either the Koch or Mech people were Kshatriyas who ran away from the fear of extermination by the Brahman sage Parashurama and took shelter in Western Assam and Northern Bengal and later disguised themselves as Mlechchas.
This process of hinduisation was much slower in the lower strata of the society,"So among the mass people the process of Hinduization was slower than in the folds of the royal family. With the embracing of Hinduism, they were left with a somewhat despised name 'Koch' and adopted the name Rajbansi, a Kshatriya status which means literally 'of royal race', confined predominantly within the cultivators and the respectable classes. The name Koch was used by the palanquin bearers. Thus Koch Behar was undergoing religious transformation and developing a caste hierarchy under an impact of Brahminical Hinduism though it was much slower in the lower strata of the society