The five events that made the United States a superpower are the:
1. Rise of USA's Economy after the events of World War 1
2. USA's role in World War 2 that toughens their standing as one of the most powerful country
3. After events in World War 2 where USA helped to rebuild Europe and gained economic power and influence
4. United Nations and North Atlantic Treaty Organization that is mostly founded and controlled by USA along with other founding nations.
5. The fall of the USSR during Cold War.
This 5 events made the USA a superpower because of USA's victorious battle against its enemy countries and World Wars, its big economy that boomed in several decades and helped many countries, and their founding of several national organizations that caters to every country.
Many indentured servants chose to move to Pennsylvania would be my guess. I can't be completely sure.
