At the time of Indian independence, India was divided into two sets of territories, the first being the territories under the control of the British Empire, and the second being the territories over which the Crown had suzerainty, but which were under the control of their hereditary rulers. In addition, there were several colonial enclaves controlled by France and Portugal. The political integration of these territories into India was a declared objective of the Indian National Congress, which the Government of India pursued over the next decade. Through a combination of factors, Vallabhbhai Patel and V.P. Menon convinced the rulers of the various princely states to accede to India. Having secured their accession, they then proceeded to, in a step-by-step process, secure and extend the central government's authority over these states and transform their administration until, by 1956, there was little difference between the territories that had formerly been part of British India and those that had been part of princely states. Simultaneously, the Government of India through a combination of diplomatic and military means acquired de facto and de jure control over the remaining colonial enclaves, which too were integrated into India.

Although this process successfully integrated the vast majority of princely states into India, it was not as successful in relation to a few states, notably the former princely states of Kashmir, Tripura and Manipur, where active secessionist movements exist.