The Library was established by the will of Dr Daniel Williams, the leading London nonconformist minister of his day, who died in January 1715/6. He left instructions for his trustees to house his library and to make it available to his fellow nonconformist ministers in London, but his provisions were inadequate, and the opening of the Library in Red Cross Street, Cripplegate, in 1729 was largely due to the efforts of his trustees who raised the necessary funds for a library building.
The collections were greatly enlarged over the years with many important gifts, and William’s original benefaction of about 7600 books forms only a small part of the modern library. The Library remained in Red Cross Street until 1865, when the Metropolitan Railway Company bought the library premises. The Library removed temporarily to No.8, Queen Square, and in 1873 to a new building in Grafton Street. The Trustees acquired University Hall in Gordon Square, London, where the Library opened in 1890. The Library is still administered by an independent Trust, and receives no government or outside funding.