Jimmu-Tennō is believed to be a descendent of the sun goddess, Amaterasu, and the very first Emperor of Japan, dating back to around 660 BCE. The Japanese recalled him in their propaganda as evidence of their purity. 

Hirohito was the ruling emperor of Japan during WWII and the 124th emperor of Japan. He was never tried for war crimes, as were many generals and other heads of State, and he retained the throne and title of Emperor after the war until his death. His son, Akihito, then became emperor.

 William Frederick Halsey Jr. achieved the rank of Fleet Admiral during WWII and was one of the key military leaders in the Pacific theater. He took part, among others, in the battles of Guadalcanal and Leyte Gulf. Much of his language regarding his Japanese enemy was racially charged, and because of it he is often quoted throughout the book.