[Thousands of photographs and illustrations of World War II are in my World War II In View Flickr collection.]
Regarding type of war outbreak (fourth column):
A = Attack without a declaration of war
U = State of war emerged through ultimatum
WD = State of war emerged after formal declaration of war
D = Diplomatic breakdown leading to a state of war.
In some cases a diplomatic breakdown later led to a state of war. Such cases are mentioned in the comments.
|
Date |
Attacking Nation(s) |
Attacked Nation(s) |
Type |
Comments |
|
1939-09-01 |
Germany |
Poland |
A |
|
|
1939-09-03 |
United Kingdom, France |
Germany |
U |
|
|
1939-09-03 |
Australia, New Zealand |
Germany |
WD |
|
|
1939-09-06 |
South Africa |
Germany |
WD |
|
|
1939-09-10 |
Canada |
Germany |
WD |
|
|
1939-09-17 |
Soviet Union |
Poland |
A |
|
|
1939-11-30 |
Soviet Union |
Finland |
A |
Diplomatic breakdown day before |
|
1940-04-09 |
Germany |
Denmark, Norway |
A |
|
|
1940-05-15 |
Germany |
Belgium, Netherlands |
WD |
The German offensive in western Europe |
|
1940-06-10 |
Italy |
France, United Kingdom |
WD |
At a time when France already was about to fall |
|
1940-06-10 |
Canada |
Italy |
WD |
|
|
1940-06-11 |
South Africa, Australia, New Zealand |
Italy |
WD |
|
|
1940-06-12 |
Egypt |
Italy |
D |
|
|
1940-07-04 |
United Kingdom |
France* |
A |
Vichy France Navy and colonies were attacked by UK, but no war was declared |
|
1940-10-28 |
Italy |
Greece |
U |
|
|
1941-04-06 |
Germany |
Greece |
WD |
|
|
1941-04-06 |
Germany, Bulgaria |
Yugoslavia |
A |
|
|
1941-04-06 |
Italy |
Yugoslavia |
WD |
|
|
1941-04-10 |
Hungary |
Yugoslavia |
A |
|
|
1941-04-23 |
Greece |
Bulgaria |
D |
|
|
1941-06-22 |
Germany*, Italy, Romania |
Soviet Union |
WD |
*The German declaration of war was given at the time of the attack |
|
1941-06-24 |
Denmark |
Soviet Union |
D |
Denmark was occupied by Germany |
|
1941-06-25 |
Finland |
Soviet Union |
A |
Second war between these nations. |
|
1941-06-27 |
Hungary |
Soviet Union |
WD |
Diplomatic breakdown 1941-06-24 |
|
1941-06-30 |
France |
Soviet Union |
D |
|
|
1941-12-07 |
United Kingdom |
Romania, Hungary, Finland |
U |
Diplomatic breakdowns 1941-02-11,1941-04-07 and 1941-08-01 |
|
1941-12-07 |
Japan |
United States |
A |
WD came the day after. |
|
1941-12-08 |
Japan |
United Kingdom |
WD |
|
|
1941-12-08 |
Canada, South Africa |
Japan |
WD |
|
|
1941-12-08 |
China |
Germany*, Italy*, Japan |
WD |
*Diplomatic breakdown 1941-07-02 |
|
1941-12-09 |
Australia, New Zealand |
Japan |
WD |
|
|
1941-12-11 |
Germany, Italy |
United States |
WD |
|
|
1941-12-12 |
Romania |
United States |
WD |
|
|
1941-12-13 |
Bulgaria |
United Kingdom, United States |
WD |
|
|
1941-12-13 |
Hungary |
United States |
WD |
|
|
1942-01-24 |
United States |
Denmark |
D |
|
|
1942-05-28 |
Mexico |
Germany, Italy, Japan |
WD |
Diplomatic breakdowns in all three cases 1941 |
|
1942-08-22 |
Brazil |
Germany, Italy |
WD |
Diplomatic breakdowns 1942-01-20 and 1942-01-28 |
|
1942-11-09 |
France |
United States |
D |
|
|
1943-01-20 |
Chile |
Germany, Japan, Italy |
D |
|
|
1943-09-09 |
Iran |
Germany |
WD |
Diplomatic breakdown in 1941 |
|
1943-10-13 |
Italy |
Germany |
WD |
After the fall of Mussolini, Italy changed side |
|
1944-01-10 |
Argentina |
Germany, Japan |
D |
|
|
1944-06-30 |
United States |
Finland |
D |
|
|
1944-08-04 |
Turkey |
Germany |
D |
Turkey declared war on Germany on 23 Feb. 1945; a state of war against Germany existed from this date. |
|
1944-08-23 |
Romania |
Germany |
WD |
Like Italy, Romania also changed side. |
|
1944-09-05 |
Soviet Union |
Bulgaria |
WD |
|
|
1944-09-07 |
Bulgaria |
Germany |
D |
|
|
1945-02-24 |
Egypt |
Germany*, Japan |
WD |
*Diplomatic breakdown already 1939 |
|
1945 |
Argentina, Paraguay, Peru, Venezuela, Uruguay, Syria, and Saudi Arabia |
Germany |
WD |
Needed a declaration to be eligible to join United Nations |
|
1945-04-03 |
Finland |
Germany |
WD |
Diplomatic breakdown in 1944, last outbreak in Europe. |
|
1945-07-06 |
Brazil |
Japan |
WD |
|
|
1945-07-17 |
Italy |
Japan |
WD |
|
|
1945-08-08 |
Soviet Union |
Japan |
WD |
Last outbreak of war during the Second World War. |