The wave of Indian immigration occurred during the nineteenth and early twentieth centuries. The government of Nepal or its agents encouraged many Indian migrants to move into the Terai for settlement. It also has to beared in mind that most of the borders of Nepal and India lied inside Nepal long ago. So to argue who moved from where is very fuzzy. Still in the early 1990s, this group mostly consisted of landless tenants and farmers from northern India's border states of Bihar and Bengal. After the fall of monarchy in Nepal, these poor immigrants managed to acquire citizenship.
Most of the Indian immigrants in Nepal, were primarily agriculturalists, although a majority of them also relied on other activities to produce supplementary income. They generally raised some farm animals, particularly water buffalo, cows, goats, and sheep for domestic purposes. The Paharis traditionally have occupied the vast majority of civil service positions because of their historical roots but there was very little involvement of Indian immigrants in Nepal's politics as they are recent arrivals.
Anti-India sentiment in Nepal is partly driven by history. The root of the problem lies in the settlement of Indian immigrants in the Terai region of Nepal. Indigenous Nepalese people residing mostly in the hill areas have resented their presence. The Tharus are the original inhabitants of Terai Regions of Nepal and consider other immigrants as Indian immigrants. They feel the Terai population exercises a disproportionate influence over Nepalese politics and economy. They also feel that the Indian immigrants in Terai Region are newly settled, and that there was no existence of them in past.