The Kamata kingdom (pron: ˈkʌmətɑ:, Assamese: কমতা ৰাজ্য) appeared in the western part of the older Kamarupa kingdom on the Indian subcontinent in the 13th century, after the fall of the Pala dynasty. The rise of the Kamata kingdom marked the end of the ancient period in the History of Assam and the beginning of the medieval period. The last rulers were the Khens, who were later displaced by Alauddin Hussain Shah, the Turko-Afghan ruler of Gauda. Though Hussain Shah developed extensive administrative structures, he could not maintain political control and the control went to the Koch dynasty.
The Koches called themselves Kamateshwars (the rulers of Kamata), but their influence and expansions were so extensive and far-reaching that their kingdom is sometimes called the Koch Kingdom. In the same century the kingdom split in two: Koch Bihar and Koch Hajo. The eastern kingdom, Koch Hajo, was soon absorbed into the Ahom kingdom in the 17th century. The western portion of the Kamata kingdom, Koch Bihar, continued to be ruled by a branch of the Koch dynasty and later merged with the Indian territory after the independence of India from the British domain.
See: Khen dynasty
The Khen dynasty ruled from their capital in Kamatapur (Gosanimari) now in Cooch Behar District. The last king, Nilambar (1480-1498), expanded the kingdom to include the present Koch Bihar districts of West Bengal and the undivided Kamrup and Darrang districts of Assam and northern Mymensing in Bangladesh as well as eastern parts of Dinajpur district.