Tripura a hilly, picturesque, princely state was first conquered by the Britishers in 1761. However, no political agent was appointed till 1871 and the Maharaja ruled hill territory " Hill Tipperah " almost independently. The State acceded to the Indian union on 13.08.1947, the agreement of merger being signed on 09.09.1949. The administration was formally taken over on 15.10.1949.Tripura, initially a one district state, was trifurcated into three Districts w.e.f. 01.09.1970. The North Tripura District started functioning in the office of the Sub-divisional officer at Kailashahar and partly at Kumarghat, later the whole office was shifted to Kailashahar. The Collectorate was shifted to the newly constructed complex at Gournagar  on 13.11.1987, subsequently North Tripura District has been bifurcated and a new District namely "DHALAI DISTRICT " has been inaugurated on 14.04.1995 with  district head quarter at Ambassa.