Memel was a part of German Reich until the end of World War I. In the 1919 Versailles Treaty the Memel area was given to Lithuania. The inhabitants of Memel were mainly Germans.
After successfully annexing Austria, Sudetenland and Bohemia-Moravian provinces, Hitler gave an ultimatum to Lithuania, in which he demanded Memel province to be returned to Germany. Lithuania agreed and Memel was reunited to German Reich.
Hitler never "invaded" Memel, although this was Nazi Germany's last bloodless conquest.
czechoslovakia
Austria
ITALY Swiss. ALPS NEPAL PAKISTAN. AND Yugoslavia
Austria, Czecoslovakia, Poland, France, Netherlands, Belgium, Luxembourg, Denmark, Norway, Danzig, Memel Territory, Yugoslavia, Greece, Estonia, Latvia, Lithuania, USSR, Channel Islands and Italy
The Battle of Britan, the air war over England.
Hitler did not invade North Korea.
Hitler did invade the USSR on 22 June 1941.
No
About half of Europe.
Yes
Yes
No
Hitler first annexed Austria.
No
Poland
1939 Poland
Operation Barbarossa was Hitler's plan to invade the USSR. It was, and still is, the largest land invasion in history.