Answer: Religious freedom.
Step-by-step explanation:
The biggest factor because people migrated to North America from America en masse, leaving England, is religion. Under the Reformation's influence, the Puritans came into conflict with the Church of England because of their religious structure. Representatives of secular authorities were also on the side of church leaders. The Puritan church structure did not suit the Puritans, and they continuously pointed out certain irregularities in the organization of that institution. Due to the impossibility of influencing the mentioned currents, the Puritans left England and went to the New World. In North America, they organize the church the way they want, and their daily lives were imbued with religious principles.