The area of the present district was an integral part of the Chutiya kingdom during the medieval period. After the defeat of the Chutias, the Ahoms placed "Sadiya-khowa gohain" to rule the region. Later, the Matak kingdom rose in its place after the Moamoria rebellion. The ancient name of Tinsukia city was "Bengmara". It was later made the capital of the Motok Kingdom when a member of the former Chutia royal family named Sarbananada Singha established his capital at Rangagarh situated in the bank of river Guijan. In 1791 AD, he transferred his capital to the city of Bengmara. Bengmara was built by King Sarbananda Singha with the help of his Minister, Gopinath Barbaruah (alias Godha). The city was built in the middle of the present city of Tinsukia. It was declared the 23rd district of Assam on 1 October 1989 when it was split from Dibrugarh.