The Purchase of the Danish West Indies.

Charles Callan Tansill (1890-1964) was professor of history at American University, Fordham University, and Georgetown University and an accomplished historian in his own right who authored 14 major historical works. In addition, he worked as the official historian for the United States Senate and in that capacity, was the final editor the classic "Documents Illustrative of the Formation of the Union of the American States," published by the Library of Congress. By the 1930s, he had been promoted to the office of advisor to the United States Senate Committee on Foreign Relations. His access to documents from the very highest levels of government afforded him a unique insight into the generation of American foreign policy in the period leading up to World War II, and he made active use of this material in preparing "Back Door to War." Tansill died of a heart attack in 1964 at the age of 73, and is buried at Oak Hill Cemetery in Washington, D.C.