Early missionary activity has been significant for aborigines by contibuting to both repression and cultural survival. Within the missions, aborigines were offered refuge from the violence of the frontier; often however, the price of safety was oppression of their belief systems and culture. The first person to be appointed as a missionary to the aborigines was Reverend William Walker in 1821. Walker believed the nomadic style of the aborigines was not compatible with Christianity so subsequently, he influenced churches to begin establishing mission stations in the 1820s. They were to train the aboriginal people in civilisation and "christian ways". In 1838, a new policy of 'protection' missions was introduced. From the perspective of the missionaries, this policy would benefit aboriginal people. They would offer protection from white man's violence and from the dangerous spread of European diseases by placing the aborigines on isolated mission stations. When assimilation became government policy in the early 20th century missionaries changed the way that they operated. Their focus shifted to assisting the assimilation of mixed raced children into white society. Many part aboriginal children were removed from their families and from the late 1950s aborigines were encouraged sometimes forcefully, to leave the missions on which they lived and try to survive in the White community. Those who left the missions were not allowed to come back and visit family still living there. A good example of how the important network of kinship groups was destroyed by early missionary activity. From the church's viewpoint, this separation from traditional cultural influences was necessary in order to provide opportunities for the missionaries to replace non christian values with christian ones. Ultimately, although the early missionaries tried to protect and assist Aboriginal people, they also had harmful effects on indigenous spirituality and culture.