Congregationalist polity, often known as congregationalism, is a system of church governance in which every local church congregation is independent, ecclesiastically sovereign, or "autonomous". Its first articulation in writing is the Cambridge Platform of 1648 in New England. Among those major Protestant Christian traditions that employ congregationalism are those Congregational Churches known by the "Congregationalist" name that descended from the Independent wing of the Anglo-American Puritan movement of the 17th century, Quakerism, the Baptist churches, and most of the groups brought about by the Anabaptist movement in Germany that migrated to the U.S. in the late 18th century. More recent generations have witnessed also a growing number of non-denominational churches, which are most often congregationalist in their governance. In Christianity, congregationalism is distinguished most clearly from episcopal polity, which is governance by a hierarchy of bishops. But it is also distinct from presbyterian polity, in which higher assemblies of congregational representatives can exercise considerable authority over individual congregations.