Kokrajhar town is the headquarter of Bodoland Territorial Council, created on 10th February, 2003 comprising of four districts viz. Kokrajhar, Chirang, Baska, Udalguri on the north bank of Brahmaputra within Assam.

Kokrajhar was originally a part of the undivided Goalpara district.In 1957 it was carved out as a Civil Sub-division from the then Dhubri Sub-division of Goalpara district. Till then, it was merely small town with a railway station.On 1st July, 1983 it was upgraded into a district. At that time, there were four Police stations viz. Bijni, Sidli, Kokrajhar and Gossaigaon with a total area of 4,065.88 Sq.Km. spreading from the river Manas in the east to the river Sonkosh in the west. In 1989, the district of Bongaigaon was carved out with about 40% area of Kokrajhar district. Later on, the Nayekgaon G.P. of Dhubri district with an area of 40.22 Sq.Km. was merged with this district. Again on 10th February, 2009 Chirang district was created by carving out parts of Kokrajhar district and some parts of Dhubri district were merged with Kokrajhar district. The present area of the district is estimated to be 3,169.22 Sq.Km.

The country of Bhutan is intricately linked with the district of Kokrajhar in many vital aspects of life of the people living both in the Bhutan hills and the plains of Kokrajhar district. There is hassle-free movement of the people across the international border for the purpose of business and tours. The Bhutanese town of Gelephu is a nice place to visit from Kokrajhar as it is just across the international boundary. There is a fine road leading from the Shyamthaibari point on the National Highway 31(C) to Gelephu. Further on, inside Bhutanese territory, there is the town of Sarphang that also can be visited via Gelephu.

The colourful Bodo community comprises the majority in Kokrajhar district. It also has a sizeable Rajbongshi and Santhal population.