WWIINaval Archives
1939 - 1945

Naval Timeline

Chronology of the defining naval conflicts, strategic shifts, and technological milestones that shaped the war at sea.

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1939

September 1

Invasion of Poland

Germany invades Poland, starting World War II. The Kriegsmarine's primary early role is coastal defense and commerce raiding.

September 3

Battle of the Atlantic Begins

The longest continuous military campaign of WWII begins as German U-boats attempt to sever British supply lines.

December 13

Battle of the River Plate

The German pocket battleship Admiral Graf Spee engages British cruisers and is subsequently scuttled in Montevideo.

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1940

April 9

Operation Weserübung

Germany invades Denmark and Norway. The Kriegsmarine suffers heavy losses, including the heavy cruiser Blücher, but secures vital ports.

May - June

Dunkirk Evacuation

Operation Dynamo rescues over 338,000 Allied troops. E-boats and U-boats harass the evacuation fleet.

November 11

Battle of Taranto

British carrier aircraft severely damage the Italian fleet. This battle heavily influences Japanese planning for Pearl Harbor.

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1941

May 24

Battle of the Denmark Strait

The German battleship Bismarck sinks HMS Hood, shocking the British public.

May 27

Sinking of the Bismarck

After a relentless pursuit, British forces cripple and sink the Bismarck, effectively ending German surface raiding.

December 7

Attack on Pearl Harbor

The Imperial Japanese Navy (Kido Butai) launches a surprise carrier strike on the US Pacific Fleet, bringing the US into the war.

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1942

May 4-8

Battle of the Coral Sea

The first naval battle where opposing fleets never saw each other, fought entirely by carrier aircraft. A tactical Japanese victory but strategic Allied win.

June 4-7

Battle of Midway

The turning point of the Pacific War. The US Navy sinks four Japanese fleet carriers (Akagi, Kaga, Sōryū, Hiryū), crippling the Kido Butai.

August

Guadalcanal Campaign Begins

A massive, brutal series of naval surface actions and carrier battles fought around the Solomon Islands, resulting in heavy losses for both sides.

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1944

June 19-20

Battle of the Philippine Sea

The "Great Marianas Turkey Shoot." US forces decimate Japanese naval aviation, effectively eliminating the IJN's carrier strike power.

October 23-26

Battle of Leyte Gulf

The largest naval battle in history. The IJN commits its remaining surface fleet, including Yamato, but suffers a crushing defeat.

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1945

April 7

Operation Ten-Go

The battleship Yamato is sent on a suicide mission to Okinawa but is intercepted and sunk by massive waves of US carrier aircraft.

September 2

Formal Surrender

Japan formally surrenders aboard the battleship USS Missouri in Tokyo Bay, ending World War II.