History of Assam Rule unfurls its chapter with the treaty of Yandabo coming into force on the 24th February 1826, the sun of the 600 year old rule of the Ahoms set and Assam lost its sovereignty. Along with a few other north eastern states Assam went under British rule up to the 15th August 1947, the day India got liberated. Yet the rule of the Ahoms in Assam for long 600 years with varying power is a historical wonder. What caused fall of the kingdom was severe infighting among the nobles of the state in later part of their rule. Secondly in later pars of its rule, clash with the Satras (religious centres spreading Vaishnavism in Assam) gave rise to civil up surges in the kingdom in the shape of Moamorian Rebellion which weakened both the political power and the socio-economical structure of the state rendering total incapability to the Ahom force to resist foreign aggressions particularly the aggressions of the Burmese (Maan) which broke the backbone of the Ahom monarchy.

Ancient history of Ahom Rule
The Ahoms arrived with the knowledge of the technology of wet rice cultivation that they shared with other groups. The peoples that took to the Ahom way of life and polity were integrated into their fold in a process of Ahomization. As a result of this process the Barahi people, for instance, were completely subsumed, and some of other groups like some Nagas and the Maran peoples became Ahoms, thus enhancing the Ahom numbers significantly. This process of Ahomization was particularly significant till the 16th century, when under Suhungmung, the kingdom made large territorial expansions at the cost of the Chutiya and the Kachari kingdoms.

Rang Ghar, a pavilion built by Pramatta Singha (also Sunenpha; 1744-1751) in Ahom capital Rongpur, now Sibsagar; the Rang Ghar is one of the earliest pavilions of outdoor stadia in South Asia. The expansion was so large and so rapid that the Ahomization process could not keep pace and the Ahoms became a minority in their kingdom. This resulted in a change in the character of the kingdom and it became multi-ethnic and inclusive. Hindu influences, which were first felt under Bamuni Konwar at the end of the 14th century, became significant. The Assamese language entered the Ahom court and co-existed with the Tai language. The rapid expansion of the state was accompanied by the installation of a new high office, the Borpatrogohain, at par with the other two high offices and not without opposition from them. Two special offices, the Sadiakhowa Gohain and the Marangikowa Gohain were created to oversee the regions won over from the Chutiya and the Kachari kingdoms respectively. The subjects of the kingdom were organized under the Paik system, initially based on the phoid or kinship relations, which formed the militia. The kingdom came under attack from Turkic and Afghan rulers of Bengal, but it withstood them. On one occasion, the Ahoms under Tankham Borgohain pursued the invaders and reached the Karatoya River, and the Ahoms began to see themselves as the rightful heir of the erstwhile Kamarupa Kingdom.

Later history of Ahom Rule
The kingdom came under repeated Mughal attacks in the 17th century, and on one occasion in 1662, the Mughals under Mir Jumla occupied the capital, Garhgaon. The Mughals were unable to keep it, and in at the end of the Battle of Saraighat, the Ahoms not only fended off a major Mughal invasion, but extended their boundaries west, up to the Manas river. Following a period of confusion, the kingdom got itself the last set of kings, the Tungkhungia kings, established by Gadadhar Singha.

The rule of Tungkhungia kings was marked by peace and achievements in the Arts and engineering constructions. The later phase of the rule was also marked by increasing social conflicts, leading to the Moamoria rebellion. The rebels were able to capture and maintain power at the capital Rangpur for some years, but were finally removed with the help of the British under Captain Welsh. The following repression led to a large depopulation due to emigration as well as execution, but the conflicts were never resolved. A much weakened kingdom fell to repeated Burmese attacks and finally after the Treaty of Yandabo in 1826, the control of the kingdom passed into British hands.