The American Congregational Union was formed in 1853 to promote Congregationalism in the United States, primarily through the construction of Congregational churches.
 In 1892, its name was changed to the Congregational Church Building Society.
 It was an agency of the National Council of Congregational Churches.
John Park Davies (1879 - 1937) was a Welsh Unitarian minister.
 He grew up in the Llandysul area, and attended the local Board School and County School, before gaining a place at the University College of Wales, Aberystwyth, from where he graduated in 1902, with a B.A. (Hons.)
 in Semitic Languages.
 In 1902 he began studies at Manchester College, Oxford, and in 1904 was awarded the Russell Martineau Hebrew prize, followed by the (university) Hall-Houghton Syriac prize in 1905.
 He subsequently commenced studies at Harvard University, from where he graduated in 1907.
 In 1908 he took up the position of Unitarian minister of Pontypridd, relocating in 1913 to take charge of the Old Presbyterian Chapel, Nantwich, and to Gateacre Chapel, Liverpool, in 1924.
William Bourne Oliver Peabody (July 9, 1799 - May 28, 1847) was a Unitarian minister and author in Springfield, Massachusetts, USA.
 His twin brother, Oliver William Bourne Peabody, was also a Unitarian minister at Burlington, Vermont, with identical birth and death years.
The Federal Street Church (established 1729) was a congregational unitarian church in Boston, Massachusetts.
 Organized in 1727, the originally presbyterian congregation changed in 1786 to "Congregationalism", then adopted the liberal theology of its fifth Senior Minister, William Ellery Channing, (1780-1842).
 For most of the 18th century the church was known as the Long Lane Meeting-House.
 In 1788, state leaders met in the relatively spacious building to determine Massachusetts' ratification of the United States Constitution.
 Thereafter the church renamed itself the Federal Street Church in honor of the event.
 In 1803, it called William Ellery Channing, (1780-1842), as its minister who defined "Unitarian Christianity" and launched the Unitarian movement, making the Federal Street Church one of the first to define itself as Unitarian.
Reverend Abiel Abbot (December 14, 1765 – January 31, 1859) was a Unitarian minister and founder of the first tax-funded free public library.
 He was born in 1765 to Abiel and Dorcas Abbot in Wilton, New Hampshire.
 He graduated from Harvard University in 1787, and received his D.D. in 1838.
 In 1827 he was installed as the minister of the Congregational Church in Peterborough, New Hampshire.
 He continued to minister until his retirement in 1849.
John Hassler Dietrich (1878–1957) was a Unitarian minister, born at Chambersburg, Pennsylvania, is called the "Father of Religious Humanism".
 He was educated at Franklin and Marshall College and at the Lancaster Theological Seminary in Lancaster, Pennsylvania, ordained in the ministry of the Reformed Church in 1905, and defrocked in 1911 for failing to affirm primary Christian beliefs.
 His religious development evolved to Humanism and Unitarianism, in which he served various pastorates, including First Unitarian Society of Spokane (1911-1916), and then First Unitarian Society of Minneapolis (1916-1938).
 He retired to Berkeley, California, where he died.
 He is buried in the crypt of First Unitarian Church of Chicago.
 He was the author of:
David Rhys Williams (1890 – March 28, 1970) was an American Congregational and Unitarian minister who wrote a Marlovian book called "Shakespeare Thy Name Is Marlowe".
Raymond Bennett Bragg (1902–1979) was an American Unitarian minister who played a key role in the writing of the Humanist Manifesto and eventually signing Humanist Manifesto.
 Raymond Bragg was born in Massachusetts and attended Bates College and Brown University.
 In 1927, he earned a B.A. in philosophy from the University of Chicago and a B.D. from Meadville Theological School and was ordained at the Unitarian Church of All Souls in Evanston, Illinois where he was pastor until 1930.
 From 1930-1935 he served as the Secretary of the Western Unitarian Conference.
 During these years he was also the editor of The New Humanist, and was one of the signers of the Humanist Manifesto, which helped give rise to a new humanist movement within Unitarianism.
 He served as pastor of the First Unitarian Society of Minneapolis from 1935–1947.
 He was the Executive Director of the Unitarian Service Committee from 1947-1952, and then became the pastor of All Souls Unitarian Church, Kansas City, Missouri, where he remained until his retirement in 1973.
 During this time, he chaired the Kansas City's Civil Liberties Union, worked on the local and state levels to improve mental health services, and was an assistant professor of philosophy at the Kansas City Art Institute.
 Upon his retirement, he was elected Minister Emeritus by the Kansas City congregation.
Von Ogden Vogt (February 25, 1879 – August 2, 1964) was a Unitarian minister.
 His theory of worship influenced the shape of mainline Protestant worship in the early 20th century, and he was an authority on the theory of worship and an influential voice in the gothic revival in church architecture in the mid-20th century, a professor at Chicago Theological Seminary and Beloit College.
 From 1925 to 1944 he was minister of The First Unitarian Church of Chicago.
 He served on the 1937 hymnal commission that produced a common hymnal for Unitarians and Universalists prior to their merger into the Unitarian Universalist Association.
The Marlovian theory of Shakespeare authorship holds that the Elizabethan poet and playwright Christopher Marlowe was the main author of the poems and plays attributed to William Shakespeare.
 Rather, the theory says Marlowe did not die in Deptford on 30 May 1593, as the historical records state, but that his death was faked.

Question: Around which famous playwright does this theory, written by American Congregational and Unitarian minister, revolve?
Answer: William Shakespeare