Australian history can be summarised as the story of how Aboriginal peoples lost a continent and how the invaders gained one. The history of colonial and State authority over Aborigines—of institutionalisation, law enforcement, detention, imprisonment, md the role of police—have been fundamental in shaping their lives. Australia's past cannot be truly understood unless it is analysed as a colonial history, and as the founding premise of Australian colonialism, terra nullius shaped the way this history unfolded. Aboriginal people as a group have been the target of various forms of discipline and surveillance-starting often through the barrel of a gun during the 'frontier' eras, then changing into the restrictions affecting mobility and personal liberty policed by mission and reserve authorities. While the aim of a gaol punishment for non-Aboriginal people was to deprive the offender of individual liberty, this was not considered enough to bring home any message to Aboriginal people.