This book addresses a neglected aspect of the history of Britain’s centuries-long involvement with transatlantic slavery. For a half century after the Slavery Abolition Act of 1833, individual Britons and British enterprises continued to own enslaved people and invest in slavery in Brazil. This book explores the material basis of this entanglement, in the context of British anti-slavery policy, to explain how the last vestiges of British slaveholding in the Americas were only extinguished by abolition in Brazil in 1888.