The settlers didnt understand the aboriginals and thought they had no religion because they couldnt relate, for example there were no buildings (churches) and they couldnt understand their language..As a result of this aboriginal people suffered greatly, there was masive loss of life amognst indigenous populations and europeans brought new diseases to the land. Loss of life grealty affected social systems such as marriage, marriage systems could no longer function properly and the inheritance of rights was disrutped. The chain of knowledge between elders and the young was lost. Abiriginal people were driven off their land, they lost homes, food sources, medicines and other natural resources. etc etc
although late, there was also the continuing effect that colonisation had on Aboriginal people. The effect on social indicators for example, such as health, crime, housing, etc. you would also do well to comment on things such as land rights and native title. Remamber, just the # was over the last 200 years, don't forget the continuing effect on Aboriginal identity etc. well.... if you still need it