The transmigration programme was initially an initiative by the Dutch colonial government, while Indonesia was under Dutch rule, as an attempt to move people over from the overly populated areas of Java to the less densely populated areas of Sumatra and Kalimantan. This programme was later continued by the Indonesian government and transmigration activity peaked from 1967-1998 during the rule of president Suharto due to the then rapidly increasing levels of industrialisation and urbanisation.
However, this programme had adverse effects on the environment, contributing to deforestation which meant a shrinking habitat for the orangutans. For many of the transmigrants who moved to these less developed areas, agriculture meant survival for them. On top of forests already being cleared by the government to create living space for these transmigrants, this population inflow meant an increase in illegal logging and slash-and-burn activities due to increasing numbers of palm oil plantations. This further accelerated deforestation and orangutans were forced to retreat to the remaining forested areas of the islands.