Explanation:

Causes of Tribal Movements.
Imposition of Land Revenue Settlement: Expansion of agriculture by the non- tribals to tribal area or over forest cover let to the erosion of tribal traditions of joint ownership and increased the socio-economic differentiation in the egalitarian structure of the tribal society.

• Work of Christian Missionaries brought about further changes in the socio economic and cultural equation of the tribals and the mainstream society.
• Increasing demand for wood from early nineteenth century- first for the royal navy and then railways, led to increasing control of government over forest land. The establishment of the Forest department in 1864, Government Forest Act (1865) and Indian Forest Act in 1878 together established complete government monopoly over Indian forest land. Shifting Agriculture, a wide spread practice amongst the various tribal communities was banned from 1864 onwards on the reserved forest. Restrictions were imposed on the previously sanctioned timber and grazing facilities.
• Extension of settled agriculture led to influx of non tribals in the tribal areas. These outsiders exploited them, and extension of settled agriculture led to the loss of land by the tribals which reduced them to agricultural labourers.

Some of the tribal uprising took place in reaction to the effect of the landlords to impose taxes on the customary use of timber and grazing facilities, police exaction, new excise regulations, exploitation by low country traders and money lenders, and restrictions on shifting cultivation in forest.
Do you know?
•The rebellions by the non-frontier tribals were usually reactions against outsiders (dikus), local landlords and rulers, the support provided to the later by the British administration and intervention by them in the life of the tribals. The indigenous names for these tribal movements were Meli, Hool and Ul-Gulan.
THINK!
•Nature of tribal movements.