William Oldys was born, most probably in London, the illegitimate son of Dr William Oldys, chancellor of Lincoln diocese and grandson of Reverend William Oldys who was brutally murdered by the Roundheads in the English Civil War. In 1724 he went to stay with Thomas Watson-Wentworth, who became the 1st Earl of Malton in 1728, at his estate Wentworth Woodhouse near Rotherham where he remained for six years.
On his return to London he was shocked to discover that his landlord had destroyed most of his valuable collection of rare books and manuscripts. In 1731 he sold the remainder to the bibliophile and patron of the arts Edward Harly, 2nd Earl of Oxford, who employed him as library secretary in 1738 to look after his substantial library of ancient books. When Harly died three years later he worked for various booksellers but by the end of the 1740’s he had fallen on hard times and spent two years in the Fleet prison for debt. Thanks to his debts being settled by his friends he was released and in 1755 was appointed Norflok Herald Extraordinary by the Duke of Norfolk and also the Norroy King of Arms.
As a bibliographic writer his whole career was devoted to the assembling and cataloguing of book collections and from 1747 until his death he was the founding editor of Biographies Britannica. Also, in collaboration with Samuel Johnson, he collated and edited the Harleian Miscellany, a collection of material from libraries of the Earl of Oxford and Earl Mortimer. He produced the British Librarian, a review of scarce and valuable books in print and manuscript, contributed to numerous biographies between 1747 and 1760 and in 1736 produced an edition of Sir Walter Raleigh’s History of the World, with a life of the author.
His poetic output was limited and his best known poem is On a Fly Drinking out of His Cup, an Anacreontic, a poem celebrating love and wine written in the style of the Greek poet Anacreon. It was said of Oldys at the time that he was a drunkard, “much addicted to low company”, possibly resulting from his association with other inmates in Fleet prison.