Most nation-states in Asia and Africa that gained independence from colonial rulers during the middle of the 20th century are diverse in their ethnic composition. The national governments make efforts to politically integrate their constituent units in the face of the continuing resistance of several ethnic groups. India adopted various means to integrate the more than 600 princely states and other loosely administered areas. Although the issue of integration has been largely settled in the mainland, various radical groups in the Northeastern region still question the extension of the Indian state. This article provides a historical analysis of the process of integration of the various states of Northeast India.