This story of Royall Tyler is in many ways unique: an American who was almost European, a self-taught art historian who became a name to reckon with in the field of Byzantine art history, an amateur historian with a superb organizing faculty of mind, a League of Nations officer who became intimately involved with Central Europe but mainly with Hungary, an OSS officer and right-hand man of Allen Dulles during World War II, a Cold Warrior until his premature death in 1953. All this provides the basis of a good story that needs to be told, and through Tyler’s career, the European story between World War I and the early Cold War can be revisited.