A Pearl Harbor Timeline

Timeline created by F123132
In Film
  • 1937 the beginning of Pearl Harbor

    Japan invades North China from Manchuria.
  • 1940

    July: U.S. imposes trade sanctions, followed by an embargo, aimed at curbing Japan's military aggression in Asia.
  • 1941

    January: Adm. Yamamoto begins communicating with other Japanese officers about a possible attack on Pearl Harbor.
  • 1941

    February: Adm. Husband E. Kimmel assumes command of the U.S. Pacific Fleet in Hawaii. Kimmel and Lt. Gen.Walter C. Short, commanding general of the Hawaiian Department, prepare for the defense of the islands. They ask their seniors in Washington for additional men and equipment to insure a proper defense of military instillations.
  • 1941

    April: U.S. intelligence officers continue to monitor Japanese secret messages. In a program code-named Magic, U.S. intelligence uses a machine to decode Japan's diplomatic dispatches. Washington does not communicate all the available information to all commands, including Short and Kimmel in Hawaii.
  • 1941 War continues

    May: Japanese Adm. Nomura informs his superiors that he has learned Americans were reading his message traffic. No one in Tokyo believes the code could have been broken. The code is not changed.
  • Finalizing of Attack

    July: Throughout the summer, Adm. Yamamoto trains his forces and finalizes the planning of the attack on Pearl Harbor.
  • 1941 Message of Attack

    Sept. 24: The "bomb plot" message from Japanese naval intelligence to Japan's consul general in Honolulu requesting a grid of exact locations of ships in Pearl Harbor is deciphered. The information is not shared with the Hawaii's Adm. Kimmel and Gen. Short.
  • 1941

    November: Tokyo sends an experienced diplomat to Washington as a special envoy to assist Ambassador Kichisaburo Nomura, who continues to seek a diplomatic solution.
  • Japan wants the U.S. to agree to its southern expansion in Asia diplomatically but if those efforts were unsuccessful, Japan was prepared to go to war.

  • Morning of Dec 06

    At 0755, Hawaiian time, the first wave of Japanese aircraft begin the attack. Along with the ships in Pearl Harbor, the air stations at Hickam, Wheeler, Ford Island, Kaneohe and Ewa Field are attacked. The Japanese attack continues for two hours and 20 minutes. When it's over, more than 2,400 Americans are dead and nearly 1,200 wounded. Eighteen ships have been sunk or damaged. More than 300 aircraft are damaged or destroyed.
  • 1942

  • 1941

    Jan. 27: Joseph C. Grew, the U.S. ambassador to Japan, wires Washington that he has learned that Japan is planning a surprise attack on Pearl Harbor. No one in Washington believes the information. Most senior American military experts believe the Japanese would attack Manila in the Philippine Islands if war broke out.
  • November 1941

    Nov. 16: Submarines, the first units involved in the attack, depart Japan.
  • 1941

    Nov. 26: The main body, aircraft carriers and escorts, begin the transit to Hawaii.
  • 1941

    Nov. 27: Kimmel and Short receive a so-called "war warning" from Washington indicating a Japanese attack, possibly on an American target in the Pacific, is likely.
  • Night of Dec. 6, Morning of Dec. 7:

    U.S. intelligence decodes a message pointing to Sunday morning as a deadline for some kind of Japanese action. The message is delivered to the Washington high command before 9 a.m. Washington time, more than 4 hours before the attack on Pearl Harbor. But the message is not forwarded to the Pearl Harbor commanders and finally arrives only after the attack has begun.
  • WAR

    Dec. 8: President Roosevelt addresses Congress and asks for a declaration of war against Japan, which he receives.
  • 1941

    Dec. 16: Adm. Kimmel and Gen. Short are relieved of their commands.
  • 1942

    January: The Roberts Commission appointed by President Roosevelt finds Kimmel and Short in dereliction of duty and solely responsible for the Pearl Harbor disaster.
  • 1944

    January: Capt. Laurence Safford, the Navy's former chief cryptographer, discovers that officials in Washington withheld secret information from Kimmel and Short.
  • 1944

    October: A Naval Court of Inquiry finds Kimmel had not been derelict but had acted appropriately given what he knew. The Chief of Naval Operations overrules the court, saying if Kimmel had done aerial reconnaissance he might have discovered the Japanese fleet just 250 miles off Hawaii
  • 1995

    December: A Defense Department investigation finds others share the responsibility with Kimmel and Short for the Pearl Harbor disaster. It does not say who those "others" are.