* Poland (September 1, 1939)
* Denmark (April 9, 1940)
* Norway (April 9, 1940)
* Belgium (May 10, 1940)
* Netherlands (May 10, 1940)
* Luxembourg (May 10, 1940)
* France (May 10, 1940)
* United Kingdom (July 16, 1940- air raids only)
* Yugoslavia (April 6, 1941)
* Greece (April 6, 1941)
* Soviet Union (June 22, 1941)
In addition, Germany occupied or annexed parts of the following countries:
* Austria (March 12, 1938)
* Czechoslovakia (March 15, 1939)
* Romania (August 23, 1940)
* Bulgaria (March 1, 1941)
* Hungary (March 19, 1944)
Germany invaded or annexed these countries in order to gain territory, resources, and military power. By controlling these countries, Germany hoped to increase its chances of winning the war.