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The history of Assam is the history of a confluence of peoples from the east, west and the north; the confluence of the Indo-Aryan, Austro-Asiatic and Tibeto-Burman cultures. Politically, it has been invaded, but has never served as a vassal or a colony to an external power till the advent of the Burmese in 1821 and subsequently the British in 1826.
The history of Assam is known from many sources. The Ahom kingdom of medieval Assam maintained chronicles, called Buranjis, written in the Ahom and the Assamese languages. History of ancient Assam comes from rock inscriptions and the many copper plates and royal grants the Kamarupa kings issued during their reign. Protohistory is reconstructed from folklore, epics like Mahabharata, and two medieval texts compiled in the Assam regionthe Kalika Purana and the Yogini Tantra.