The 1620 agreement (first called the Mayflower Compact in 1793) was a legal instrument that bound the Pilgrims together when they arrived in New England. The core members of the Pilgrims' immigrant group were Separatists, members of a Puritan sect that had split from the Church of England, the only legal church in England at that time. Others in the group, however, had remained part of the Church of England, so not all of the Pilgrims shared the same religion.

The compact was drafted to prevent dissent amongst Puritans and non-separatist Pilgrims who had landed at Plymouth a few days earlier.

The Mayflower Compact, signed by 41 English colonists on the ship Mayflower on November 11, 1620, was the first written framework of government established in what is now the United States.