In the late eighteenth century, slave labour in Britain's colonies was seen as central to world trade, and the practice was supported by prominent members of society, including the king. Ottobah Cugoano, an emancipated slave living in England, had joined the Sons of Africa, a group whose members wrote to the royal family, aristocrats and leading politicians to condemn slavery and campaign for its abolition. This work, first published in 1787 and sent to George III, was a daring attack on colonial conquest and enslavement, arguing that slaves had a moral duty to rebel against their oppressors. Widely read upon publication, it went through at least three printings that year and was translated into French, with a shorter version published in 1791. This reissue of the original work makes available an important document in the history of colonialism and slavery in the British Empire.