The previous post is accurate in the suggestion that the War in question is probably World War II. Simply put, the unification of mainland Europe under the Nazi flag can be stated as a reality at the zenith of Hitler's power. The German army had been able to overtake many a nation on the mainland. The lone holdouts seemed to be Russia and England. The latter was subjected to an extensive bombing campaign in the hopes of bringing them to Hitler's control, and the former had an agreement of non- aggression to prevent its takeover. Only when the Nazis had violated this accord and started the process of taking up arms against Russia did they openly oppose the Nazis.
The Munich Conference of 1938 appeased Hitler by giving back the Sudetenland which Germany had lost after WWI in return for his promise not to push any further. It failed, later that year German troops entered and occupied Czechoslovakia. On 9-1-1939 Hitler invaded Poland launching a blitzkrieg (lightening war) against the nation. In addition, the following nations fell to Nazi aggression: Estonia, Latvia, Lithuania, Romania, Austria, Greece, Finland, Denmark, Norway, Netherlands, Belgium, and France. Great Britain was the only nation in Europe that did not fall to Hilter.
You say "before the Cold War." I assume you mean before World War II, since Hitler and the Nazis were defeated before the Cold War began.
Before WWII started, Hitler and the Nazis took the following lands:
- They "reunited" Germany and Austria.
- They took the Sudetenland, which was a part of Czechoslovakia mostly inhabited by Germans.
- They took all of Czechoslovakia.
I'm not sure you can say they conquered these places because they did not have to fight to take any of them. They were all taken by diplomacy.
When Germany did try to actually conquer something (Poland), the war started.
Adolph Hitler led Nazi Germany into War with many countries. He started locally in Europe and then spread out as far as he could before spreading his armies too thin. Hitler controlled Europe to include Yugoslavia, France, Serbia, Estonia, Luxembourg, Crete, Romania, Channel Islands, Poland, Germany, Czechoslovakia, Belgium, Holland, Italy, Rumania, Holland, Switzerland, Austria, and Greece.
Hitler wanted to control Russia and Africa as well. When troops went into Africa, they were able to conquer Northern Africa, but lost it away later to the Russians. Sweden and Portugal managed to remain neutral during the war.