This article will first examine colonial dispossession by highlighting the relationship between the British opium trade and intellectual property law---i.e. legal discourses of ownership---in the eighteenth and nineteenth centuries. Analysis will then proceed to settler colonial dispossessions 'then' and 'now' in twentieth and twenty first century advertising techniques---i.e. cultural discourses of ownership - for medications containing or derived from opium in the United States such as patent medications and Oxycontin. In the history of the commodification of opium in the US, we see a shift from the appropriation of indigenous culture, to the mobilisation of late liberal notions of autonomy. Tracing the history of opium across these seemingly disparate geographies and discursive registers will work to analyse discourses of ownership in US settler colonialism by addressing their relationship to discourses of ownership in earlier forms of British colonialism. This approach is taken in the spirit of Veracini's contention that if it is to be carved out as a distinct theoretical concept, settler colonialism should be considered within a dialectical relationship to colonialism.