Mir Jumla's invasion of Assam, between 4 January 1662 and January 1663, was the most intrusive of all Mughal invasions of the Ahom Kingdom in the 17th century. Led by Mir Jumla II, the subahdar of Bengal during the reign of Aurangzeb, the Mughals managed to occupy the Ahom capital of Garhgaon. Nevertheless, the distressed Mughal forces barely managed to return with a face-saving treaty."The exhausted army barely managed to struggle its way out of the region and conclude a treaty that somehow saved their face." The Ahoms agreed to a vassal status with a tributary arrangement akin to the ones the Mughal Empire had with the Rajputs; but Mir Jumla died en route to Dhaka, and the Ahoms pushed the Mughal garrisons out of Assam within four years"But torrential rains and poor communication with Dhaka, followed by famine and disease in the imperial camp, forced the Mughals to reach a tributary arrangement with the Ahom raja, similar to those that had been concluded with Rajput chieftains since the days of Akbar. In early 1663 the expeditionary force began its return to Dhaka, but Mir Jumla died en route. Within four years the Ahom kings had renewed the war, pushing Mughal garrisons out of Assam." —when Ahom forces took control up to the Manas river in December 1667.
Background The Kamata kingdom under the Koch dynasty split in 1581 into Koch Bihar, which lay to the west of the Sankosh River and Koch Hajo, which lay between the Sankosh in the west and the Kameng River in the eastNote: Raghudev's domain, Koch Hajo, consisted primarily the Undivided Goalpara district, the Undivided Kamrup district, the region east of Bornadi River up to the Bharali River (Kameng River) in addition to the region between the old Brahmaputra channel and the Garo hills, which is effectively eastern Mymensingh Division in present-day Bangladesh. —starting a bitter rivalry between two branches of the dynasty. Meanwhile, the Mughals were able to bring Bengal under some semblance of authority by 1583, though it was still being challenged by the Baro-Bhuyan of Bengal led by Isa Khan. The rivalry and conflicts between the two Koch domains continued to be hot driving Koch Bihar into Mughal vassalage and Koch Hajo to align first with Isa Khan, and when that disappeared, with the Ahoms. Eventually the Mughals under Islam Khan marched against Koch Hajo, removed Parikshit Narayan, the then ruler, and took control of his territory in 1613, bringing them into direct confrontation with the Ahoms. At this point the Koch Hajo region (or called Kamrup) ended up not with the Koch Bihar ruler but with the Mughals—and nearly took over complete control of Koch Bihar itself.
The Mughals called the newly acquired territory Villayat Koch Hajo and established four sarkars: (1) Kamrup, (2) Dhekuri, (3) Dakhinkul, and (4) Bangalbhum. The local peasants, till then under the Paik system and now without a local ruler, revolted against the Mughal system imposed on them, and gained some recognition under a peasant leader called Sanatan.
Struggle for Kamrup The Mughals now cast its imperial eye on the riches of the entire Brahmaputra valley and planned to take over the Ahom kingdom next."Soon after the conquest of Kamrup a direct Ahom-Mughal clash became inevitable. The predominant factor was the political issue. The Bengal viceroy, Qasim Khan, cherished the political ambition of continuing the imperialistic policy of his brother, Islam Khan, in the north-east to its grand final. It had proved eminently successful against Koch Bihar and Kamrup. It was expected to be equally promising with regard to the third'i.e. Assam." But the first expedition under the command of Aba Baqr in 1615 was unsuccessful, with the Ahoms routing the Mughals at the Battle of Samdhara (1616)."Though initially successful, the (first) maiden Mughal offensive in Assam was disastrous ... The losses in men and materials were colossal : about 1700 killed on the spot and 3400 died of wounds later after escape; 900 captives; about 3000 half-dead concealed. ... True, the Ahom king had not intervened in Kamrup-Mughal war, he now checked the Mughal aggression, which raised his morale, strengthened his position and added to his resources by capture of Mughal spoils - elephants, horses, war-boats, guns, swords and munition. Pratap Simha constructed a fort at Samdhara and had his exploits inscribed on rock (1616), as visama samara vijayana."
The Ahoms then started a proxy war (1616–1620) against the Mughals in Kamrup"The Ahom king incited insurrections, gave political asylum to anti-Mughal elements and supplied men, money and war materials to all appeals of help from disaffected chieftains and hill-rajas of Kamrup. In brief, the Ahom king attempted to pull the strings or attack from behind without coming out in the open. Such was the nature of Raja Pratap Simha's (160-41) unofficial war for the period 1616 to 1620." but when it failed to drive them out "So long Assam, pursued a policy of unofficial war, of indirect hostility, aiding and fighting with the Mughals on behalf of all anti-Mughal elements in Kamrup till 1620. This policy, as we have seen, was not very successful." they changed course to prepare for a more direct campaign."The integrity of Kamrup would be [the Ahom king's] imperative and efficient door-bar against the Mughals. So he changed his policy again combining open war with the Mughals needed greater strength, greater resources and greater organization. So he reorganised the structure of Ahom society, administration and army." The campaign, which began in March 1636 primarily under Bali Narayan, a scion of the Koch dynasty and the ruler of Darrang under the Ahoms, ended in December of the same year with the Ahoms gaining possession of most of Kamrup."These ten months of continuous war (March-December) were highly favourable to the Ahoms and the rebels of Kamrup. Notwithstanding a few minor defeats near Pandu and Srighat, they had come to occupy all the principal fortified outposts on both sides of the Brahmaputra, including Hajo, Pandu and Srighat. The Assamese established their sovereignty in most parts of Kamrup." This was followed immediately by a Mughal counter-campaign in December 1637 under Mir Zeiuddin and Allah Yar Khan—and by April 1638 they defeated Bali Narayan at Barpeta, recovered Hajo, defeated the Ahoms at Kajali and then began planning to take the Ahom kingdom itself."Instead of consolidating their hold and conserving their material and moral position, [the Mughals] indulged in ambitious expansionist plans at the cost of Assam." In this second attempt into the Ahom kingdom, the Mughals were aided by the ruler of Koch Bihar, Pran Narayan, but in the final battle at Duimunisila, the combined Mughal and Koch forces were defeated and this ended with the Treaty of Asurar Ali, signed between Allah Yar Khan and Momai Tamuli Borborua, which fixed the Ahom-Mughal border at the Bornadi River, the original eastern boundary of Koch Hajo. Allah Yar Khan was appointed the faujdar at Hajo, and though there were disputes, they were settled diplomatically by Allah Yar Khan on the Mughal side and Momai Tamuli Borborua on the Ahom side.
Ahoms take old Koch Hajo After Shah Jahan fell sick in 1657 Shah Shuja, the Bengal Subahdar and a claimant to the Mughal throne, left Bengal with his entire army and naval forces to participate in the war of succession leaving Sarkar Kamrup exposed. Pran Narayan, the ruler of Koch Bihar and a Mughal vassal, declared independence and moved to occupy Kamrup. His minister-general, Bhavnath Karji, came from the west and encamped at Hajo oppressing ryots and Muslim women. The Ahoms, led by Borbarua Tangsu Handikoi advanced from the east. Squeezed between the two advancing forces, the Koch from the west and the Ahoms from the east, Mir Lutfullah Shiraji, the then faujdar at Guwahati, fled to Jahangirnagar in early 1659, bringing the Koch and the Ahoms face to face. The Koch proposed a division of Kamrup but the Ahoms refused. The Ahoms then advanced against the Koch under the command of three Phukans up to the Sankosh in the west and south up to Hatshila,"The Ahoms advanced under three Phukans (Baduli, Lapeti and Phul Barua unopposed beyond Baritala and established an outpost at Hatisala only 5 stages from Dacca), prevented the Mughals from frequenting the local market, plundered Mughal Kamrup and carried away Mughal prisoners to Assam (April-May, 1660)." thus occupying the old Koch Hajo territory of Parikshit Narayan.
The Ahoms then evacuated the Mughal population in the newly occupied region to the Ahom kingdom,"[T]he Ahoms occupied the entire territory from the Barnadi to the Sankosh. Under the Ahom King's order the Barphukan and Picksai Chetia carried out a mass evacuation of the entire people (dhekeri) of Kamrup or Lower Assam up to the Saru Sankosh, its tributary, and their transportation to Assam, which resulted in depopulation and growth of jungles in the whole area for a year and a half. and installed a scion of the Koch dynasty who promised to bring a rapprochement between the Ahoms and the Koch powers as the king of the newly acquired territories."[T]he Ahom king took under his protection Jaynarayan (a loyal Koch prince) and declared him king of Kamrup with his capital at Ghila Vijaypur (July-August, 1659)."
Prelude to invasion Aurangzeb rewarded Mir Jumla for his service in the Battle of Khajwa, which Aurangzeb won against Shuja; and when Shuja began his retreat to Bengal Aurangzeb charged Mir Jumla with his pursuit. At Tanda Shuja took his last stand and then escaped to the Arakan—when Aurangzeb received this news he appointed Mir Jumla the Subahdar of Bengal in June 1660—in his farman Aurangzeb wanted Mir Jumla to conquer Assam and Arakan after settling the administration in Bengal."After the conquest of Bengal from Shuja, Aurangzeb appointed his General, Mir Jumla, Governor of Bengal (June, 1660). In his farman he wanted the Mir to conquer Assam and Arakan after settling the affairs of Bengal." Mir Jumla is said to have persuaded Aurangzeb to conquer Assam first to use as a base in future campaigns against Burma (Myanmar) and China."But it was the Mir who took the Emperor's permission to postpone the Arakan expedition and to invade Koch Bihar and Assam. ... If we believe European travellers, the Mir wanted to use Assam as a base for conquering Burma and China. According to Sarkar, Mir Jumla was motivated both by imperialist design as well as Islamic zeal."Mir Jumla was actuated not only by imperialistic designs, but,—as his trusted Waq i 'a-navis tells us —also by a desire for 'a holy war with the infidels of Assam,' and 'an ardent passion for releasing Mussalmans (prisoners of war), rooting out idolaters, lifting up the banner of Islam and destruction of the customs of unbelief and error.'"
The Koch and Ahom rulers immediately sought peace"The two offending rulers, hearing of Aurangzeb's victory and the Mir's preparations, hastened to profess peace." —but Mir Jumla understood that it was a ruse to buy time to prepare for war."Realising, however, that these peace overtures of the two rulers were mere ruses to gain time for preparations, Mir Jumla determined to strike himself first against Koch Bihar and then, if necessary, against Assam,after making suitable administrative arrangements in Bengal during his absence." In 1661 Mir Jumla sent Raja Sujan Singh against the Koch and Rashind Khan against the Ahoms; but neither of them could move far. Sujan Singh's advance stopped at Ekduar due to the rainy season." Mir deputed Raja Sujan Singh, later reinforced by Mirza Beg Shuja against the vassal Koch ruler, Pran Narayan, now seeking pardon. But Sujan singh could not proceed beyond Ek duar at the entrance to Koch Bihar (May-June, 1661) when the rains suspended all operations."