Our conversation with Don Doyle, the McCausland Professor of History at the University of South Carolina and the recent author of “The Cause of All Nations: An International History of the American Civil War,” published by Basic Books. In this interview,  Dr. Doyle discusses the power of “public diplomacy” in Europe and Latin America during the American Civil War and the power wielded by Giuseppe Garibaldi during the conflict. Additionally, Dr. Doyle discusses the evolution of rhetoric in the sphere of public diplomacy as the war shifted from one with emancipation as the chief aim to that of Union.