1. Poland (September 1, 1939)
2. Denmark (April 9, 1940)
3. Norway (April 9, 1940)
4. Belgium (May 10, 1940)
5. Netherlands (May 10, 1940)
6. Luxembourg (May 10, 1940)
7. France (May 10, 1940)
8. Yugoslavia (April 6, 1941)
9. Greece (April 6, 1941)
10. Albania (April 7, 1941)
11. Czechoslovakia (March 15, 1939)
12. Austria (March 12, 1938)
13. Ethiopia (October 3, 1935)
14. Libya (September 13, 1940)
15. Tunisia (February 14, 1943)
16. Algeria (November 8, 1942)
17. Morocco (November 8, 1942)
18. Ukraine (June 22, 1941)
19. Belarus (June 22, 1941)
20. Russia (June 22, 1941)
21. Crimea (June 22, 1941)
22. Estonia (July 7, 1941)
23. Latvia (July 10, 1941)
24. Lithuania (July 22, 1941)
25. Hungary (March 19, 1944)
26. Romania (August 23, 1944)
27. Bulgaria (September 8, 1944)
28. Finland (June 25, 1941)
In total, Germany invaded and occupied at least 28 countries during World War II.