John Oldmixon was born in Somerset, England, in 1673. Raised by the family of Admiral Robert Blake in Bridgwater, he initially engaged in trade through the port of Bristol before turning his attention to literature. His early creative endeavors focused on poetry and drama, producing works such as Amores Britannici; Epistles Historical and Gallant (1703) and the tragedy The Governour of Cyprus.
Oldmixon soon transitioned to historical and political writing, which would define his career. His early historical publications included The British Empire in America (1708), The Secret History of Europe (1712–1715), and Arcana Gallica (1714). He also became heavily involved in periodical journalism, editing publications like The Muses Mercury and The Medley, though he frequently lamented that his political services went unrewarded by the government.
His most significant, though highly partisan, contributions were his extensive works on English history. In his Critical History of England (1724–1726), Oldmixon defended Bishop Gilbert Burnet while attacking the Earl of Clarendon, sparking a public controversy with Dr. Zachary Grey. He continued this partisan approach in History of England During the Reigns of the Royal House of Stuart (1730), where he accused Francis Atterbury and other editors of altering historical texts—a charge Atterbury vigorously denied. Oldmixon completed his historical survey of England with subsequent volumes covering the Tudor and early Hanoverian eras, and his posthumous Memoirs of the Press 1710-1740 (1742) offered a final reflection on his career in print.
