Why were the Virginia House of Burgesses, the Mayflower Compact, and the John Peter Zenger trial significant?

any details are important

Why were the Virginia House of Burgesses, the Mayflower Compact, and the John Peter Zenger trial significant?
Virginia House of Burgesses – First American legislative assembly (Jamestown, 1619)





Mayflower Compact – First American constitutional document (Plymouth, 1620)





John Peter Zenger trial – Established the principle of freedom of the press (New York, 1735)