John Fenwick (baptised 1757 – 1823) was an English army officer, political radical and Irish nationalist writer.
He was a close friend of William Godwin, a loyal associate of James Coigly, and the husband of Eliza Fenwick.
[1] In mid-1801 Fenwick bought from Daniel Lovell a newspaper, the Albion and Evening Advertiser.
He ran it with Charles Lamb, but publication ceased in August of that year.
[2] Fenwick wrote for Richard Phillips a biographical sketch of William Godwin, for Public Characters of 1799–1800, from personal acquaintance, and asserting Godwin's personal fame of the period.