Why is the growth of nationalism in colonies linked to an anti colonial movement?

Growth of nationalism in colonies is linked to an anti-colonial movement. The British government in  India had for the first time unified the administration of India politically, and economically. This had been done by the railways and telegraph system .The atrocities of the government had adversely impacted all classes of Indian society. There were political associations and the socio-political leaders worked towards reformation and revival of Indian culture  which was being dominated under the Western culture. Hence, the anti colonial feelings coloured the national movement in India.