The leader during WWII who was a communist dictator and joined the Allied Powers after being invaded by Germany was Joseph Stalin.
Explanation:
1. Joseph Stalin was the leader of the Soviet Union during World War II.
2. He was a communist dictator, ruling the Soviet Union with authoritarian control.
3. Germany invaded the Soviet Union in 1941 during World War II in a massive military operation known as Operation Barbarossa.
4. Following the invasion, Joseph Stalin aligned the Soviet Union with the Allied Powers, which included countries such as the United States, the United Kingdom, and others fighting against the Axis Powers led by Germany, Italy, and Japan.
5. Winston Churchill was the Prime Minister of the United Kingdom during WWII, and Benito Mussolini was the fascist dictator of Italy, both of whom were on the opposing side to Stalin and the Soviet Union during the war.
6. Hideki Tojo was the Prime Minister of Japan during WWII and was a key figure in Japanese military decision-making during the conflict.
In summary, Joseph Stalin was the communist dictator who led the Soviet Union and joined the Allied Powers after being invaded by Germany during World War II.
