Georg Grabenhorst (1899-1997) served as a probationary officer during World War I. After the war he earned a doctorate in philosophy from the University of Kiel and served as an executive officer of the Regional History Society for Lower Saxony and, later, with the West German Ministry of Cultural Affairs. Of the numerous volumes of fiction and nonfiction he wrote, only Zero Hour was subsequently published in English. Robert Cowley is the founding editor and former editor in chief of MHQ: The Quarterly Journal of Military History. His books include The Great War: Perspectives on the First World War, No End Save Victory: Perspectives on World War II, and The Cold War. He lives in Connecticut. Casey Clabough is an assistant professor of English at Virginia's Lynchburg College.