Allied Powers = dark green
Allies after attack on Pearl Harbor = light green
Axis Powers = blue
Neutral = gray
Most countries in the world participated in WWII.
The leading Axis powers were Nazi Germany, the Kingdom of Italy, and the Empire of Japan.
The major Allied Powers were the United Kingdom and France and their colonies, China, the Soviet Union and the United States.
Ireland, Portugal, Spain, Sweden and Switzerland remained neutral. Among the neutral nations, Portugal, Sweden, and Switzerland aided the Allied Powers by supplying “voluntary” brigades to Great Britain. Spain, recovering from a calamitous civil war, generally favored the Axis Powers. Ireland generally favored the Allies.