United and uniting churches

A united church, also called a uniting church, is a denomination formed from the merger or other form of church union of two or more different Protestant Christian denominations, a number of which come from separate and distinct denominational orientations or traditions. Multi-denominationalism, or a multi-denominational church or organization, is a congregation or organization that is affiliated with two or more Christian denominations, whether they be part of the same tradition or from separate and distinct traditions.

Historically, unions of Protestant churches were enforced by the state, usually in order to have a stricter control over the religious sphere of its people, but also for other organizational reasons. As modern Christian ecumenism progresses, unions between various Protestant traditions are becoming more and more common, resulting in a growing number of united and uniting churches. Examples include the United Church of Canada (1925), the Church of South India (1947), the Evangelical Church in Germany (1948), the United Church of Christ (1957), the United Methodist Church (1968), the Church of North India (1970), the Church of Pakistan (1970), the Uniting Church in Australia (1977), the Protestant Church in the Netherlands (2004), and the United Protestant Church of France (2013).

In the developing world, this model has been attractive in countries where Protestants are a small minority of the population; by pooling resources and endorsing cross-attendance between denominations, churches can serve a wider geographical area. In the developed world, since the mid-20th century, and the rise of secularism worldwide, mainline Protestantism has shrunk, reducing the viability of many individual denominations maintaining parallel administrative structures. Among others, Reformed (Calvinist), Anglican, and Lutheran churches have merged, often creating large nationwide denominations. In some countries, Methodist and Congregational denominations have also merged. The phenomenon is much less common among evangelical, nondenominational and charismatic churches as new ones arise and many of them remain independent of each other, although in some cases instances of evangelical church congregations joining multiple denominations in a phenomenon known as "multi-denominationalism" does occur; but in most cases Evangelicals cooperate with each other through interdenominationalism while still maintaining denominational distinctions.