The Second Unitarian Church in Brooklyn was a historic church in Cobble Hill, Brooklyn, New York City, built in 1857-58 and demolished in 1962.
In the mid-nineteenth century, new religious congregations were gathering in the area because of the proximity to South Ferry and Manhattan. Immigrant centers were developing around their respective churches and more churches were being built: In 1887, the Brooklyn Daily Eagle called Clinton Street "a highway of churches," and described twelve erected between 1841 and 1869 between Pierrepont Street and Third place on Clinton Street. One of these was the Second Unitarian Church, built in 1858 on the corner of Clinton and Congress Streets.
Unitarian liberal families moved to Brooklyn mainly from New England as well as from Europe, and between 1833 and 1902 organized four congregations in Brooklyn, New York. The first service of the Unitarian Congregation in Brooklyn was held in 1833. In 1835, the congregation purchased the existing Second Presbyterian Church on Adams Street for their use. In 1837, Rev. Frederick W. Holland became a minister of the congregation. According to Olive Hoogenboom, the church biographer, Holland’s preaching was too orthodox for some of the families and the congregation divided. The new Society, called the Second Unitarian Congregational Society, formed in 1840 with Rev. Frederick A. Farley as its Minister. When Rev. Holland resigned from the First Unitarian Society in 1842, the congregations reunited for a short time, but differences in ideology opened old wounds, and in 1851 the Second Unitarian Society began to hold separate services again. For several years, in order to hold service and Sunday School, the Second Society had to rent rooms in various locations throughout Brooklyn Heights. In 1853, Rev. Samuel Longfellow became minister of the Second Church and the decision was made to build a permanent home for the congregation. This permanent church was built on the corner of Clinton and Congress streets, on property leased from the Catholic Church. Jacob Wrey Mould was chosen as an architect of the church.
One of the most prominent leaders of the Second Unitarian Church was Rev. Samuel Longfellow. Under his leadership (1853–60), the New Chapel was built giving the congregation a permanent home. Longfellow’s strong abolitionist preaching was not popular among the new members of the church. In the First Unitarian Church pamphlet printed for the occasion of the 125th anniversary, we can read “some of us went around and let all the benches, and then Mr. Longfellow preached a John Brown sermon and drove them all away.” (Chase, 8) However the liberal members of the Congregation loved their Minister. Because of Longfellow’s strong abolitionist preaching the Church was controversial and grew in debt as some members felt offended. Longfellow resigned from his ministry in the Second Church in April 1860, yet his abolitionist preachings were resounded only a year later by the start of the American Civil War. Following Rev. Longfellow, the Rev. Nahor A. Staples (1861–63) became head of the church. His preaching strongly supported abolitionism and the science of the Herbert Spencer and Charles Darwin’s discoveries. During the American Civil War, the Second Church was involved in organizing donations to the Union front. His successor, the Rev. John White Chadwick, also a supporter of Darwinism, lead the church from 1864 to 1904. He continued preaching the type of theology of previous minister’s publishing most of his sermons. Chadwick attracted many new members with his preaching and the Congregation was finally able to pay its debt in 1872. The Brooklyn Ethical Association held its first meetings in the Second Unitarian Church in 1880s having Chadwick as one of its most valuable members. The Second Church’s Female Employment Society had also grown out of “the Little Church on the Corner”. According to Olive Hoogenboom, the First Church historian, "The Second Church remained a center of controversy for half of its seventy-four-year existence" (47). After Rev. John White Chadwick, the Second Unitarian Church was led by Rev. Caleb S. S. Dutton (1907–14) who and Rev. Charles H. Lyttle (1914–24), the last minister of the Second Church that brought the two Societies together in 1924.