and Foreign Unitarian Association was founded in 1825. It has its headquarters in Essex Hall, successor to Lindsey's Essex House. Two that have been significant in national life are the Cross Street Chapel in Manchester and, Newington Green Unitarian Church in north London. Unitarian congregations in Britain today meet under the auspices of the General Assembly of Unitarian and Free Christian Churches. There are 170 communities of Unitarians across Britain. The Chief Officer of the British Unitarians was Liz Slade as of 2020. United States In the United States, the Unitarian movement began primarily in the Congregational parish churches of New England, which were part of the state church of Massachusetts. These churches, whose buildings may still be seen today in many New England town squares, trace their roots to the division of the Puritan colonies into parishes for the administration of their religious needs. In the late 18th century, conflict grew within some of these churches between Unitarian and Trinitarian factions. In 1805, Unitarians gained key faculty positions at Harvard. In 1819 William Ellery Channing preached the ordination sermon for Jared Sparks in Baltimore, outlining the Unitarian position. The American Unitarian Association was founded as a separate denomination in 1825. By coincidence and unknown to both parties, the AUA was formed on the same day—May 26, 1825—as the British and Foreign Unitarian Association. In the 19th century, under the influence of Ralph Waldo Emerson (who had been a Unitarian minister) and other transcendentalists, Unitarianism began its long journey from liberal Protestantism to its present more pluralist form. Integration, 1825–1961 After the schism in the Congregational Churches resulting in the foundation (1825) of the American Unitarian Association, some of those churches remained within the Congregational fold and became member congregations of the Congregational organization (later the United Church of Christ), while others voted to become Unitarian. Some of the latter eventually became part of the Unitarian Universalist Association (formed in 1961) during a consolidation of the Unitarian and Universalist churches. Universalist churches in contrast followed a different path, having begun as independent congregations beyond the bounds of the established Puritan churches entirely. Today, the UUA and the United Church of Christ cooperate jointly on social justice initiatives such as the Sexuality Education Advocacy Training project. In 1961 the American Unitarian Association (AUA) was consolidated with the Universalist Church of America (UCA), thus forming the Unitarian Universalist Association (UUA). In the