A Boy at War is set during the weeks surrounding the Japanese attack on Pearl Harbor on December 7, 1941. Although the attack comes as a complete shock to the story’s protagonist, Adam, and to many others on the island, tensions had been growing between the United States and Japan throughout the 1930s. The US was extending its power in the Pacific, including Hawaii, as Japan took control of territory in China, a US ally. American and Japanese diplomats tried to negotiate for a better relationship without success. By November 1941, with the US blocking crucial exports to Japan, Japanese leaders gave the order to begin preparing for the Pearl Harbor attack. They hoped that by disabling the US fleet in Hawaii, they would have a clear path to take control of Southeast Asia and Indonesia.

A Japanese fleet assembled in the Kuril Islands, northeast of Japan, and then moved toward Hawaii. From these ships, about 360 planes would be launched for the attack. Shortly before 8:00am on December 7, the first plane appeared in the sky over Pearl Harbor. The Japanese bombed airfields at the same time they dropped bombs on the naval fleet, preventing the air force from mounting an effective defense.