Dibrugarh the headquarters of the district derives its name from Dibarumukh. The name derived from the mouth (mukh) of the river Dibaru or Dibru (Bodo word Dibru, a blister). During the reign of Siuhungmung, Pharsengmung Borgohain, Chao Siulung, Kilong fought against the Chutiya King who was defeated in the battle and surrendered before the Ahom King. Dibarumukh was a renowned encampment of Ahoms during Ahom Chutia War.