Sivasagar is a town and headquarter of the Sivasagar district, Assam. Sivasagar is situated about 360 kilometers (224 mi) northeast of Guwahati. It is well known for its Ahom palaces and monuments. Sivasagar is an important centre for tea and oil industries today.
It is said that the original name of Sivasagar was – ‘Kalansupar’ after the name of ‘Kalansu Gohain’ who resided in a village that originally existed in the place where currently the Sivasagar tank is located. In the year 1733, the Ahom queen Ambika devi dug a tank at the ahom capital Rangpur, covering a area of 257 acre. The place came to be known as Sivpore (Sivpur) being associated with the great Siva temple (Siva Dol) built on the bank of this tank. Then with the passage-of time, the name Sibsagar was formed.
Sivasagar, formerly known as Rangpur, was the capital of the Ahom Kingdom from 1699 to 1788. The Ahoms ruled Assam for six centuries until their kingdom fell to the Burmese Konbaung dynasty in 1819 and their ruling class was all but wiped out.
During the reign Gaurinath Singha (1780–1795) a battle was fought against the Moamoria rebels on the vicinity of the Sivasagar tank.
The province was conquered by the British in 1825 and was completely annexed in 1826. For administrative purposes, it was divided into three sub-divisions.