This is the first book to investigate the development of antislavery thought and rhetoric within the Society of Friends. Through meticulous examination of the earliest writings of the Friends, including diaries and letters, Brycchan Carey reveals the gradual transition the organization underwent in their position on slavery: from expressing doubt about slavery to adamant opposition to it. Though the Quakers adopted a stance against slavery much earlier than the emergence of a mainstream antislavery movement, Carey demonstrates that progression towards this stance was ongoing but slow and uneven and shows that rather than either economic necessity or political expediency, it was vigorous internal debate and discussion that led Quakers to oppose the slave trade in 1761. This book will be a major contribution to the history of the rhetoric of antislavery and the development of antislavery thought as explicated in early Quaker writing.