World War I: World War I was a global conflict that began in 1914 and profoundly impacted world events, including power shifts between Europe and America.
Great Depression: The Great Depression was an economic crisis that started with the stock market crash in 1929. It had significant consequences for both Europe and America, altering their relative positions of power.
Cold War Era: The Cold War Era refers to the period of political tension and rivalry between Western powers led by the United States and Eastern powers led by the Soviet Union. This era greatly influenced global politics after 1945.