This article records tradition as it has been passed down and reported. Its sources are not yet part of the atlas's verified catalogue.
John Winthrop led a fleet of eleven ships out of Southampton in April 1630, carrying Puritan colonists who believed England's own established church had stopped short of a full reformation, to found the Massachusetts Bay Colony on Calvinist congregational lines. Massachusetts and its neighbouring colonies were governed by Puritans and largely for Puritans, and the Congregational churches they built there, self governing in their own local affairs yet doctrinally Calvinist throughout, functioned in practice as established churches, supported by public taxation the way the Church of England was supported at home.
That arrangement acquired its written constitution in 1648. The Cambridge Platform, drafted chiefly by Richard Mather and John Cotton in answer to Presbyterian critics who wanted a more centralised church government, set out congregational polity in a single settled document, fixing how a New England church chose its own minister, disciplined its own members and related to its sister congregations. It served the region as its religious constitution for well over a century afterward.
What this changed for Christianity's spread was the transplanting of Calvinist church government wholesale across the Atlantic and its establishment, by public tax support rather than mere toleration, as the practical religion of an entire English colonial region. New England's Congregational churches carried Calvin's own discipline forward under a polity distinct from Geneva's, proving the doctrine could take root and govern a society without a Consistory or a state church behind it.