Book excerpt: When abolitionists Thomas Clarkson and Ottobah Cugoano published their essays on slavery in the late eighteenth century, they became key participants in one of the most important human rights campaigns in history. British abolitionism sought to expose the realities of transatlantic slavery in addition to asking politicians to help dehumanized Africans in the New World, and this edition brings together two major essays of the 1780s that were influential in the spread of the early abolitionist movement: Clarkson’s An Essay on the Slavery and Commerce of the Human Species and Cugoano’s Thoughts and Sentiments on the Evil and Wicked Traffic of the Slavery and Commerce of the Human Species. A critical introduction and extensive historical appendices on British and American slavery and abolitionism, featuring contemporary arguments for and against slavery, are also included.