In honor of u/Tetartos_Ippeas I will occasionally repost from other fora to c/Conspiracies. This one is in light of a comment by u/no_ez.

This is expanded from an earlier post via my attempting to keep the most important details without imbalance (even though editorial decisions are unavoidable and the current list is Amerocentric).

• Constantine didn't like other Catholics and founded Roman ("Lateran") Catholics, 312.
• Roman Catholics under Damasus I and "antipope" Ursinus I didn't like each other and were briefly two churches, 366-367.
• Roman Catholics didn't like Nestorius whose church got called Church of the East, 424.
• Roman Catholics didn't like Cyril of Alexandria whose church got called Oriental Orthodox, 451.
• Roman Catholics didn't like Abraham I whose church got called Armenian Apostolic, 607.
• Roman Catholics didn't like Michael I whose church got called Eastern Orthodox, 1056.
• Roman Catholics under Innocent II and "antipope" Anacletus II didn't like each other and were briefly two churches, 1130-1138.
• Roman Catholics didn't like Peter Waldo whose church got called Waldensians ("Huguenots"), 1215.
• Roman Catholics under Urban VI and "antipope" Clement VII didn't like each other and were briefly two churches, 1378-1417.
• Roman Catholics didn't like John Wyclif whose church got called Lollards, 1381.
• Roman Catholics under Gregory XII, "antipope" Benedict XIII, and "antipope" Alexander V didn't like each other and were briefly three churches, 1409-1417.
• Roman Catholics didn't like Jan Hus whose church got called Moravians ("Hussites"), 1415.
• Roman Catholics didn't like Martin Luther whose church got called Lutherans ("Evangelicals"), 1521.
• Lutherans didn't like Conrad Grebel whose church got called Anabaptists, 1525.
• Lutherans didn't like Huldrych Zwingli whose church got called Zwinglians ("Calvinists"), 1529.
• Henry VIII didn't like Roman Catholics and founded Anglicans ("Episcopals"), 1534.
• Menno Simons didn't like Roman Catholics and founded Mennonites, 1536.
• Shimun VIII didn't like Church of the East so Roman Catholics founded Chaldean ("Malabar") Catholics for him, 1553.
• John Knox didn't like Roman Catholics and founded Presbyterians, 1560.
• Anglicans didn't like Richard Fitz and John Browne whose church got called Congregationalists ("Brownists", "Independents", "United Church of Christ"), 1567.
• Roman Catholics didn't like Gaspar van der Heyden, Jean Tan, and Joannes Polyander, whose church got called Reformed, 1571.
• Anglicans didn't like Henry Barrow and John Greenwood whose church got called Separatists ("Barrowists", "Pilgrims"), 1587.
• Anglicans didn't like John Smyth whose church got called Baptists, 1607.
• Johann van Oldenbarnevelt didn't like Calvinists and founded Remonstrants ("Arminians"), 1610.
• Henry Jacob didn't like Anglicans and founded Calvinist ("Particular", "Reformed") Baptists, 1616.
• Anglicans didn't like Hamlet Jackson and Dorothy Traske whose church got called Seventh Day Baptists, 1616.
• Congregationalists didn't like Roger Williams whose church got called American Baptists, 1638.
• Gerrard Winstanley and William Everard didn't like Anglicans and founded Levellers ("Diggers"), 1649.
• Anglicans didn't like George Fox whose church got called Friends ("Quakers"), 1650.
• Paul Palmer didn't like other Baptists and founded Free Will Baptists, 1702.
• Alexander Mack didn't like Roman Catholics and founded German Baptists ("Church of the Brethren"), 1708.
• Roman Catholics didn't like Jakob Ammann whose church got called Amish, 1712.
• Roman Catholics didn't like Cornelius Steenoven and Dominique Varlet whose church got called Old Catholics ("Independent Catholics"), 1724.
• Eastern Orthodox didn't like Cyril VI so Roman Catholics founded Melkite Greek Catholics for him, 1729.
• Ebenezer and Ralph Erskine didn't like other Presbyterians and founded Associate Reformed Presbyterians ("United Secession Church", "United Free Church"), 1733.
• Anba Athanasius briefly didn't like Eastern Orthodox so Roman Catholics founded Coptic Catholics for him, 1741.
• Thomas Nairn didn't like Presbyterians and founded Reformed Presbyterians ("Covenanters"), 1743.
• Other Baptists didn't like George Whitefield whose church got called Second Baptist ("Separate Baptists"), 1743.
• James and Jane Wardley didn't like Quakers and founded Believers ("Shakers"), 1747.
• John Wesley didn't like Anglicans and founded Methodists ("Wesleyans"), 1784.
• Martin Boehm didn't like Mennonites and Philip Otterbein didn't like Reformed, and they founded United Brethren, 1800.
• Barton Stone didn't like Presbyterians and founded Churches of Christ, 1803.
• Methodists didn't like Hugh Bourne and William Clowes whose church got called Primitive Methodists, 1807.
• Presbyterians didn't like Thomas Campbell whose church got called Disciples of Christ, 1809.
• Anthony Groves didn't like Anglicans and founded Plymouth ("Open") Brethren, 1825.
• Quakers didn't like each other, and their churches got called Orthodox Quakers ("Friends United Meeting") and Hicksite Quakers ("Friends General Conference"), 1827.
• Reformed didn't like Samuel Frohlich whose church got called Apostolic Christians ("Evangelical Baptists", "New Anabaptists"), 1830.
• Lutherans didn't like Johann Scheibel whose church got called Wisconsin Synod ("Independent Evangelical", "Old") Lutherans, 1832.
• Reformed didn't like Hendrik de Cock whose church got called Christian Reformed, 1834.
• Other Lutherans didn't like Carl Walther whose church got called Missouri Synod Lutherans, 1839.
• David Welsh, Thomas Chalmers, and Robert Candlish didn't like Presbyterians and founded Free Church of Scotland, 1843.
• Albany Conference didn't like Baptists and founded Adventists ("First-Day"), 1845.
• William Johnson didn't like other American Baptists and founded Southern Baptists, 1845.
• John Wilbur didn't like Friends United and founded Conservative Friends ("Wilburite Quakers"), 1847.
• John Darby didn't like Open Brethren and founded Exclusive ("Darbyist") Brethren, 1848.
• Methodists didn't like James Everett, William Griffith, and Samuel Dunn, whose church got called United Methodist ("Reform"), 1849.
• Gilbert Cranmer didn't like Adventists and founded Church of God (Seventh Day), 1858.
• Southern Baptists didn't like James Graves whose church got called Landmark Baptists ("Bride"), 1859.
• Other Methodists didn't like Benjamin Roberts whose church got called Free Methodists, 1860.
• Jonathan Cummings didn't like Adventists and founded Advent Christians, 1860.
• Ellen White didn't like other Adventists and founded Seventh-Day Adventists, 1863.
• William and Catherine Booth didn't like Methodist Reform and founded Salvation Army, 1865.
• George Hoffman didn't like United Brethren and founded United Christians, 1877.
• German Baptists didn't like Samuel Kinsey whose church got called Old German Baptists, 1881.
• German Baptists didn't like Henry Holsinger whose church got called Brethren Church, 1882.
• Baptists didn't like Richard Spurling whose church got called Church of God ("Cleveland"), 1886.
• Charles Spurgeon didn't like other Baptists and founded Independent ("Fundamental") Baptists, 1887.
• Albert Simpson didn't like Presbyterians and founded Christian and Missionary Alliance, 1887.
• Donald MacFarlane didn't like Free Church of Scotland and founded Free Presbyterian Church of Scotland, 1893.
• William McAlpine, William Simmons, and Bishop Johnson didn't like other American Baptists and founded National Baptists, 1895.
• Charles Parham didn't like Methodists and founded Apostolic Faith ("Assemblies of God"), 1895.
• Joseph Widney and Phineas Bresee didn't like Methodists and founded Church of the Nazarene, 1895.
• Baptists didn't like Charles Jones and Charles Mason whose church got called Church of God in Christ, 1896.
• Benjamin Young, Benjamin Irwin, and Abner Crumpler didn't like Methodists and founded Fire Baptized Holiness ("Pentecostal Holiness"), 1896.
• Southeastern Kansas Fire Baptized Holiness Association didn't like Fire Baptized Holiness and founded Bible Holiness ("Wesleyan Fire Baptized Holiness"), 1898.
• Nicholas Tolstoy didn't like Eastern Orthodox so Roman Catholics founded Russian Catholics for him, 1905.
• William Fuller didn't like Fire Baptized Holiness and founded Fire Baptized Holiness Church of God, 1908.
• James Wedgwood didn't like Roman Catholics and founded Liberal Catholics, 1917.
• Karel Farsky didn't like Roman Catholics and founded Czechoslovak Hussites, 1920.
• Watson Sorrow and Hugh Bowling didn't like Pentecostal Holiness and founded Congregational Holiness, 1921.
• Aimee Semple McPherson didn't like Assemblies of God and founded Foursquare, 1923.
• Union Bible College and Oregon Yearly Meeting didn't like Friends United and founded Central Friends and Evangelical Friends, 1926.
• Geevarghese Ivanos didn't like Eastern Orthodox so Roman Catholics founded Malankara Catholics for him, 1930.
• Baptist Bible Union didn't like other American Baptists and founded Regular Baptists, 1932.
• Seventh-Day Adventists didn't like Victor Houteff whose church got called Davidians, 1934.
• Herbert Armstrong didn't like Church of God (Seventh Day) and founded Grace Communion International ("Worldwide"), 1934.
• Gresham Machen didn't like other Presbyterians and founded Orthodox Presbyterians, 1936.
• Carl McIntire, Oliver Buswell, and Allan MacRae didn't like Orthodox Presbyterians and founded Bible Presbyterians, 1937.
• Louis Bauman and Charles Ashman didn't like German Baptists and founded Grace Brethren ("Charis"), 1939.
• Roman Catholics didn't like Carlos Duarte Costa whose church got called Brazilian Catholic Apostolic, 1945.
• Liberal Catholics didn't like other Liberal Catholics and founded Liberal Catholics International, 1947.
• Hilmer Sandine didn't like other Congregationalists and founded Conservative Congregational Christian Conference, 1948.
• Roman Catholics didn't like Michel Collin whose church got called Apostles of Infinite Love, 1951.
• Harry Johnson didn't like other Congregationalists and founded National Association of Congregational Christian Churches, 1955.
• Glenn Griffith didn't like Church of the Nazarene and founded Bible Missionary, 1955.
• Benjamin Roden didn't like other Davidians and founded Branch Davidians, 1955.
• Toma Darmo didn't like Church of the East and founded Ancient Church of the East, 1964.
• Chuck Smith didn't like Foursquare and founded Calvary Chapel, 1968.
• Marcel Lefebvre didn't like Roman Catholics and founded Society of Saint Pius X, 1970.
• North American Christian Convention didn't like Disciples of Christ and founded Independent Christians, 1971.
• Jack Williamson didn't like other Presbyterians and founded Presbyterian Church in America, 1973.
• William Kohn didn't like Missouri Synod Lutherans and founded Evangelical Lutherans, 1976.
• Clemente Dominguez y Gomez didn't like Roman Catholics and founded Palmarian Catholics, 1978.
• Calvary Chapel didn't like John Wimber whose church got called Vineyard, 1982.
• Clarence Kelly didn't like Society of Saint Pius X and founded Society of Saint Pius V, 1983.
• Francesco Ricossa didn't like Society of Saint Pius X and founded Institute of the Mother of Good Counsel, 1985.
• Alexander Murray didn't like Free Presbyterians and founded Associated Presbyterians, 1989.
• Roman Catholics didn't like George Stallings whose church got called African-American Catholics, 1990.
• David Bawden didn't like Roman Catholics and founded Conclavists, 1990.
• John Whitcomb didn't like other Grace Brethren and founded Conservative Grace Brethren, 1992.
• Lucian Pulvermacher didn't like Roman Catholics and founded True Catholics, 1998.
• Mike Bickle didn't like Vineyard and founded International House of Prayer, 1999.
• Free Church of Scotland didn't like Free Church Defence Association whose church got called Free Church of Scotland (Continuing), 2000.
• WordAlone Network didn't like Evangelical Lutherans and founded Lutheran Congregations, 2001.
• Robert Nemkovich didn't like Old Catholics and founded Polish National Catholics, 2003.
• Oscar Michaelli didn't like Roman Catholics and founded Catholic Apostolic Remnant, 2006.
• Paull Spring didn't like Evangelical Lutherans and founded North American Lutherans, 2010.
• Keith Boyette didn't like United Methodists and founded Global Methodists, 2022.
• Laurent Mbanda didn't like other Anglicans and founded Global Anglicans, 2025.

This leaves out movements, including both cults, and movements like evangelical and born-again; it also leaves out much that could be said (including lateral transfers, mergers, and dissolutions), but I'm trying to focus on schisms that are close to the trunk.