John Elliot Cairnes (1823 1875) was one of the leading economists of his day, holding professorships at Trinity College Dublin, University College, Galway, and University College, London. He gained an international reputation with The Slave Power, first published in 1862, and enlarged and reissued the following year. His analysis of the economic and social system of the Confederate states in America did much to influence British support for the Union in the United States' Civil War. He argued that the course of history was influenced most of all by economic causes. Although he had begun his study of the slave trade on a theoretical basis, the outbreak of civil war had given it a more immediate and practical application. His case is very clearly and impartially argued. While being opposed to slavery on moral grounds, he fairly states the arguments on both sides, and refutes some of the Confederate propaganda.