Baack (born May 13, 1943) is an American historian of modern Europe, with a particular interest in Germany and Scandinavia, and a sub-specialty in Antarctica.
He is the author of Agrarian Reform in Eighteenth Century Denmark, Christian Bernstorff and Prussia: Diplomacy and Reform Conservatism 1818-1832, and Undying Curiosity: Carsten Niebuhr and the Royal Danish Expedition to Arabia 1761-1767, among other works.