Columbia subject headings:
Benedict XV, Pope, 1854-1922.
Catholic Church--Foreign relations.
Catholic Church--History--20th century.
World War, 1914-1918--Diplomatic history.
World War, 1914-1918--Peace.
Harvard subject headings:
Benedict XV, Pope, 1854-1922
Catholic Church--Foreign relations.
Catholic Church--History--20th century.
World War, 1914-1918--Diplomatic history
World War, 1914-1918--Peace
Princeton subject headings:
Benedict XV, Pope, 1854-1922.
Catholic Church and world politics--History--20th century.
World War, 1914-1918--Catholic Church.
World War, 1914-1918--Peace.