Published in Japanese in 1949, Citadel in Spring is, at its heart, an autobiographical novel of the author's life from university through induction into the Imperial Japan Navy , assignment to intelligence service in China, and Japan's final defeat. In addition to details of actual code-breaking activities, it also paints grimly honest pictures of some of the fiercest naval battles of the war, and the horrors of the Hiroshima atomic bombing. As a witness to World War II and its effects on the people and culture of Japan, this document-although cast as fiction-is a crucial reminder of the real costs of war to a generation who have never experienced it.