Congregational churches are Protestant Christian churches practicing Congregationalist church governance, in which each congregation independently and autonomously runs its own affairs.
Congregational churches became widely established in the Massachusetts Bay Colony, later New England. The model of Congregational churches was carried by migrating settlers from New England into New York and the Old Northwest: Ohio, Indiana, Michigan and Illinois. With their insistence on the independence of local bodies, they became important in many reform movements, including those for abolition of slavery, and women's suffrage. As of the early 21st century, Congregationalism in the U.S. had split into three major bodies: the United Church of Christ, which most local Congregational churches affiliated with, the National Association of Congregational Christian Churches, a fellowship of churches and individuals formed to continue and foster classic Congregationalism as the merger that created the UCC was being debated, and the Conservative Congregational Christian Conference, an evangelical group.
According to the congregationalist understanding of the history of the Christian Church, the early disciples of Jesus had little or no organization. Congregationalists believe that in the centuries after the spread of Christianity, leaders in centers like Rome, Antioch, Alexandria, Byzantium, and Jerusalem attempted to gain influence over all the churches in certain regions by creating hierarchy and structure. Typically, congregationalists viewed this accumulation of power to be complete by the year AD 1000, with the bishop of Rome claiming authority over all Christendom. Many churches throughout the western part of Europe submitted to his authority. The churches of eastern Europe, all of Asia, and Egypt likewise had been gathered under hierarchies of bishops, but retained independence from the Pope, according to this view.
Congregationalism is more easily identified as a movement than a single denomination, given its distinguishing commitment to the complete autonomy of the local congregation. The idea that each distinct congregation fully constitutes the visible Body of the church can, however, be traced to John Wycliffe and the Lollard movement, which followed Wycliffe's removal from teaching authority in the Roman Catholic Church.
In England, the Anglican system of church government was taken over by the king, Henry VIII. Influenced by movements for reform and by his desire to legitimize his marriage to Anne Boleyn in 1533 (without the blessing of the Pope in Rome) after divorcing his first wife Catherine of Aragon, Henry's government influenced Parliament to enact the 1st Act of Supremacy in 1534. It declared the reigning sovereign of England to be 'the only supreme head on earth of the Church in England.' In the reign of Elizabeth I, this title was changed to Supreme Governor of the Church of England, an act still in effect. The Church of England thus replaced Catholicism as the established state religion.
With the demise of the monarchy, the Westminster Confession of Faith (1646) was officially declared the statement of faith for both the Church of England (Anglican) and Church of Scotland (Presbyterian). In 1658 the Congregationalists created their own version of the Westminster Confession, called the Savoy Declaration. The underground churches in England and exiles from Holland provided about 35 out of the 102 passengers on the Mayflower, which sailed from London in July 1620. They became known in history as the Pilgrim Fathers. The early Congregationalists sought to separate themselves from the Anglican church in every possible way and even forwent having church buildings. They met in homes for many years.