​SIBSAGAR, a town and district of British India, in eastern Bengal and Assam. The town is situated on the Dikhu river, about 9 m. from the left bank of the Brahmaputra, being picturesquely built round a magnificent tank, covering an area of 114 acres. Pop. (1901) 5712. In 1907 the transfer of the district headquarters to Jorhak (pop. 2899), on the Disai river, was sanctioned.

The District of Sibsagar has an area of 4996 sq. m. It consists of a level plain, much overgrown with grass and jungle, and intersected by numerous tributaries of the Brahmaputra. It is divided by the little river Disai into two tracts, which differ in soil and general appearance. The surface of the eastern portion is very flat, the general level being broken only by the long lines of embankments raised by the Ahom kings to serve both as roadways and as a protection against floods. The soil consists of a heavy loam of a whitish colour, which is well adapted for rice cultivation. West of the Disai, though the surface soil is of the same character, the general aspect is diversified