At the same time as the "Red Scare," the USA was experiencing the worst racial violence in its history. Hundreds were killed. Some claimed, without evidence, that the Bolsheviks were behind it.
Labor unrest, racial violence, and anarchist bombs were blowing up across the USA in 1919, making many people wonder if the Bolsheviks were behind it all.
Political violence in Mexico tapers off after the new constitution comes into effect, although Venustiano Carranza will not give up power willingly.
The technological end economic changes wrought by the Great War will have major impacts even on nations that remained neutral.
The compromise under which Japan got the German concession in China was bitterly resented in China and led to a backlash against the West.
The Japanese, like the Italians, had territorial demands they wanted the peace conference to recognize. They also wanted the League of Nations to embrace racial equality.
With Italian politics becoming increasingly polarized between violent extremes, the environment is perfect for the rise of Mussolini.
After Italy's postwar territorial demands were rejected by the other Allies, Prime Minister Orlando and the Italian delegation walked out of the peace conference.
The standoff between the Turks and what remained of the Allies (Greece, backed up by Britain) leads to war.