Kamarupa and Assam
At the time of the advent of the Muslims in Bengal in the early thirteenth century, the Brahmaputra valley was parcelled out into a number of independent principalities, at war with one another. A line of Chutiya (a tribe of mixed Bodo-Shan stock) kings ruled over the tract east of the Subansiri arid the Disang, while a strip to the south and southeast was under the control of some Bodo tribes. Further west was a Kachari kingdom lying south of the Brahmaputra and extending probably half way across the Nowgong district. West of the Chutiyas on the north bank and of the Kacharis on the south, were the domains of some petty chiefs called Bhuiyas.
To the extreme west was situated the kingdom of Kamarupa, the western boundary of which was marked by the river Karatoya and the eastern boundary varied according to the position of its hostile neighbours. It was known as the kingdom of Kamata. The Ahoms, a section of the great Shan tribe, had appeared as a new element in the history of the Brahmaputra valley early in the thirteenth century, and checked the eastern expansion of the Kamata kingdom, while its western neighbours, the Muslim Sultans of Bengal, led several invasions into its territories with varying results.
Early in the fifteenth century a strong monarchy was established in Kamata by the Khens with their capital at Kamatapur, a few miles to the south of Cooch Bihar. The Khens ruled over Kamata for about seventy-five years and their last ruler, Nilambar, was overthrown by ‘Ala-ud-din Husain Shah in about A.D. 1498. After a short period of confusion, Biswa Simha, of the Koch tribe, which was Mongoloid in origin, established a powerful kingdom with Koch Bihar, modern Cooch Bihar, as his capital, about A.D. 1515. The greatest ruler of this line was Biswa Simha’s son and successor, Nara Narayan, during whose reign the kingdom of Kamata grew in prosperity, and reached the zenith of its power. But in 1581 he was compelled to code the portions of his kingdom to the east of the river Sankosh to his nephew, Raghu Dev. Thus the Koch kingdom was divided into two rival principalities, called Koch Bihar and Koch Hajo by the Muslims. Their feuds drew the intervention of the Ahoms and the Muslims, and in 1639 the western and the eastern States fell under the supremacy of the Muslims and the Ahoms respectively.
The Ahoms, a section of the Shan tribe, who appeared in Assam in about A.D. 1215, gradually consolidated their position and established a strong monarchy which lasted for six centuries. During the period under review they checked the eastward expansion of the kings of Kamarupa and the Sultans of Bengal. The kingdom of the Ahoms became vulnerable to Muslim attacks only after the latter had subjugated Kamarupa, Thus ‘Ala-ud-din Husain Shah of Bengal led an expedition into Assam when it was ruled by Suhenpha. In spite of the initial success of Muslim arms, this expedition had a disastrous end. There was no Ahom-Muslim conflict for more than thirty years, till the second phase of it began when invasions into Ahom were conducted by some local Muhammadan chieftains of Bengal. But their attempts also failed by September, 1533. Thus the attempt of the Muslims of Bengal to conquer Assam ended in failure by the thirties of the sixteenth century.
Nepal
By the year A.D. 879 Nepal possibly threw off the Tibetan yoke and came to have an independent history of its own. For two hundred years after this we know little about the kings ruling in Nepal, but from the eleventh century Nepal flourished under the Thakuris. For more than two hundred years (1097-1326), the Karnataka king Nanyadeva of Mithila and his successors claimed, from their capital at Simraon, a sort of loose sovereignty over the local princes of Nepal. In A.D. 1324, Harisimha of Tirhut, a descendant of Nanyadeva, invaded Nepal, the reigning king of which, Jayarudramalla, submitted to him. With his headquarters at Bhatgaon, Harisimha gradually extended his power over the whole valley, and his kingdom had diplomatic relations with China in the fourteenth century. But at the same time Harisimha and his descendants “left undisturbed the local rulers, who acknowledged their hegemony, in the possession of the two other capitals, viz., Patan and Katmandu”. About 1370 A.D. Jaya-Sthitimalla, grandson-in-law of the Malla king, Jayarudra (1 320-1326), and son-in-law of Jagatsimha, a prince of the Karnataka line of Harisimha, who had married Jayarudra’s daughter, Nayakadevi, seized the throne of the Mallas and by 1382 established his authority over practically the whole of Nepal. It was henceforth ruled by his descendants “in regular succession”. He had three sons-Dharmamalla, Jyotirmalla and Kirtimalla. They kept the kingdom undivided. By A.D. 1418 Harisimha’s descendants lost their authority in NepaI, and Jyotirmalla tried to exercise imperial power. About A.D. 1426 Jyotirmalla was succeeded by his eldest son,Yakshamalla, who ruled for more than half a century and was the greatest of the Malla rulers of NepaI. But he made a mistake before his death, about 1480, in partitioning the kingdom among his sons and daughters. This led to the rise of the two rival principalities of Katmandu and Bhatgaon, whose quarrels ultimately led to the conquest of Nepal by the Gurkhas in A.D. 1768.