A Library Born From the British Museum

For most of its existence the national library of the United Kingdom was not a separate institution at all. When the British Museum was founded in 1753 around the bequeathed collection of Hans Sloane, its library department held the printed books and manuscripts alongside the Museum's antiquities and natural history specimens under one roof and one board of trustees, an arrangement that lasted for more than two centuries. The library department grew through the same channels as the rest of the Museum's collection: royal and aristocratic donations, purchase, and the acquisition of private libraries and manuscript collections, including Sir Robert Cotton's library of medieval manuscripts and Hans Sloane's own manuscript holdings, both of which had entered the Museum at or near its founding.

The British Library Act 1972 separated the library department into an independent national library, which opened to readers as the British Library in 1973 and moved into its own purpose built building at St Pancras, completed in 1997, ending the long period in which the Museum's Reading Room served as the library's public face. The split left the British Museum with its antiquities, art and archaeological collections and gave the new British Library the printed books, manuscripts, maps and the legal deposit function, the statutory right to a copy of every book published in the United Kingdom and Ireland, that keeps the collection growing today. The manuscript and rare book holdings the Library inherited from the Museum's eighteenth century founding collections did not change hands again in the split; only the institution around them did.