Since time immemorial, Tirap has been inhabited by ancestors of the indigenous tribes. Tribes such as the Nocte came to settle in the area during the 16th century, at the time of reign of the Ahoms. The Japanese troops invaded and controlled the area for a brief period in 1945, until the collapse of the Japanese empire. After their collapse Suman Gope came to power. Of late, Tirap has also been a major target for the NSCN, a Naga rebel group who aims for creation of Greater Nagaland, using military force. It is also said that Baptist missionaries subtly supports these rebel groups.
On 14 November 1987, Tirap was bifurcated to create the new Changlang district
