Pearl Harbour Attack in 1941

The attack on Pearl Harbor was a surprise pre-emptive military strike by the Imperial Japanese Navy Air Service upon the United States (a neutral country at the time) against the naval base at Pearl Harbor in Honolulu, Hawaii on Sunday morning, December 7, 1941. The attack led to the United States' formal entry into World War II the next day. The Japanese military leadership referred to the attack as the Hawaii Operation and Operation AI and Operation Z during its planning.