Joseph Smith, a portion of whose collection formed the foundation of King George III.'s library, now in the British Museum, was born in 1682. Nothing appears to be known about his parents and his early years, but at the age of nineteen he took up his residence at Venice, where he spent his life, apparently engaged in commerce.[68] In 1740 he was appointed British Consul in that city, and he died there on the 6th of November 1770, aged eighty-eight.

Smith was well known as a collector of books, manuscripts, and works of art. In 1762 George III. purchased all the books Smith had amassed up to that time for about ten thousand pounds, and at a later period the king also bought his pictures, coins, and gems for the sum of twenty thousand pounds. After the sale of his library Smith still continued to collect, and the books which he subsequently acquired were sold after his death, partly by auction by Baker and Leigh at their house in York Street, Covent Garden, on Monday, January 25th, 1773, and the thirteen following days, and partly in the shop of James Robson, bookseller, in New Bond Street. Those sold by Baker and Leigh realised two thousand two hundred and forty-five pounds. A portion of his manuscripts was purchased by the Earl of Sunderland for one thousand five hundred pounds. Smith's library was rich in the best and scarcest editions of Latin, Italian and French authors. It also contained a considerable number of fine manuscripts, some of them beautifully illuminated, and many valuable books of prints and antiquities.

About 1727 Smith compiled a catalogue, which was limited to twenty-five copies, of some of the rarest books in his collection, of which a second edition with additions was published in 1737. A catalogue of his entire library was printed at Venice in 1755, and in 1767 an account of his antique gems in two volumes folio, written by Antonio Francesco Gori, was published in the same city under the title of Dactyliotheca Smithiana. An edition of Boccaccio's Decamerone was brought out by Smith in 1729.