What are three characteristics that differentiate the literature of American romanticism from the literature of early America and the colonial period?

During the American colonial period, nearly every colonist was puritanical, and they were very strict in their abiding by the Old Testament in the Christian Bible. However, American romanticism basically went against every practice of Puritanism, creating works of absurd fictions, such as epics and fantasies. Edgar Allen Poe is one of the most renowned romanticism authors in the world. Shakespeare is another, even though he obviously wasn't American.