United and uniting churches

The first union of churches in the world to cross historical denominational lines (1925) — Methodist, Presbyterian majority, and Congregationalist, driven by the practical demands of ministry across the Canadian west; the continuing Presbyterian minority is the pattern-case of the union-remainder rule.

The coerced union: Japan's wartime state compelled Protestant merger in 1940–41 to control the churches; when the law fell in 1945, the Episcopal, Lutheran, part of the Baptist and Holiness bodies, and the Salvation Army withdrew — the tree's standing witness that union by decree is not oneness. Remains Japan's largest Protestant body.

The first union since the Reformation between episcopal and non-episcopal churches — Anglican, Methodist, Presbyterian, and Congregational traditions in one body, simultaneously a member of the Anglican Communion, the World Methodist Council, and the WCRC; the tree's clearest multi-trunk confluence. Separation: the Anglican Church of India (1964) — union-remainder pattern.

The 1957 union of the Congregational Christian and Evangelical & Reformed churches — the first American union across differing polities and historical backgrounds, framed by its founders as a step toward healing the Reformation's divisions.

The 1970 six-tradition union of northern India's Protestant churches — Anglican, Methodist, Presbyterian/Congregational, Disciples, Baptist and Brethren streams — a province of the Anglican Communion and member of the World Methodist Council and WCRC; the Church of Pakistan (1970, including Lutherans) and Church of Bangladesh (1974) are its sibling unions.

The 1970 union of Anglicans, Church of Scotland Presbyterians, Methodists, and Lutherans in Pakistan — the united-church family's rare four-trunk node including the Lutheran line.

England and Wales's 1972 Reformed union, later gathering the UK Churches of Christ (1981) and Scottish Congregationalists (2000); its own 2022 General Assembly reported about one-fifth of its formation membership remaining — stated on the node without editorializing.

Australia's 1977 three-tradition union, deliberately named 'Uniting' rather than 'United' — union as an ongoing posture, not an accomplished event; its census-identification decline (870K in 2016 to 673K in 2021) beside 243K members is a clean self-identification-versus-membership exhibit for the methodology page.

The 2004 Dutch union healing the 19th-century secessions and joining the Lutherans besides — and, within a week, minting two continuing denominations (Restored Reformed Church; Continued Reformed Churches, May 8, 2004): the union-remainder pattern at its sharpest.