Answer:
He claimed the Frontier Thesis or Turner Thesis and it is is the argument advanced by historian Frederick Jackson Turner in 1893 that American democracy was formed by the American frontier.
Hope this helps if not I’m sorry
An international conflict taking place in northern Europe from 1618 to 1648. The war was fought between Catholics and Protestants and also drew in the national armies of France, Sweden, Spain, Denmark, and the Habsburg dynasty that ruled the Holy Roman Empire.
