John Longe (1548–1589) was an English Protestant archbishop of Armagh.
He was born in London, and educated at Eton College where he was a King's Scholar. He later attended King's College, Cambridge, where he was admitted a scholar on 13 August 1564; there is no record that he took a degree.
After taking holy orders and holding many livings in England, he was promoted to the see of Armagh and primacy of all Ireland in July 1584, on the nomination of Sir John Perrot, Lord Deputy of Ireland. He was made a member of the privy council in Ireland in 1585, and died at Drogheda in 1589, being buried in Primate Octavian's vault at St Peter's, Drogheda. Lord Deputy William Fitzwilliam, in a letter dated 12 February 1589, to William Lyon, bishop of Cork, remarked that he "loved good cheer but too well."
- Harwood, Thomas (1797-01-01). Alumni Etonenses: Or, A Catalogue of the Provosts & Fellows of Eton College & King's College, Cambridge, from the Foundation in 1443 to the Year 1797 : with an Account of Their Lives & Preferments, Collected from Original Mss. and Authentic Biographical Works. T. Pearson.
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- "Long, John (LN564J2)". A Cambridge Alumni Database. University of Cambridge.