Kamarupa, an early state during the Classical period on the Indian subcontinent, was (along with Davaka) the first historical kingdom of Assam. Though Kamarupa prevailed from 350 CE to 1140 CE, Davaka was absorbed by Kamarupa in the 5th century CE. Ruled by three dynasties from their capitals in present-day Guwahati, North Guwahati and Tezpur, Kamarupa at its height covered the entire Brahmaputra Valley, North Bengal, Bhutan and northern part of Bangladesh, and at times portions of what is now West Bengal, Bihar and Sylhet.

Though the historical kingdom disappeared by the 12th century to be replaced by smaller political entities, the notion of Kamarupa persisted and ancient and medieval chroniclers continued to call a part of this kingdom Kamrup. In the 16th century the Ahom kingdom came into prominence and assumed for themselves the legacy of the ancient Kamarupa kingdom and aspired to extend their kingdom to the Karatoya River.