McParlan records that a member of the Keon family, a minor, was a non-resident proprietor in Leitrim in 1802. However, he also records Mr. Keon, of Keonbrook, on his list of "resident gentlemen of property". William Keon offered for sale lands in the baronies of Carrigallen and Mohill in the Encumbered Estates Court in February 1855. In the 1870s the representatives of Ferdinand Keon, living in London, owned over 200 acres in county Leitrim while other members of the Keon family held over 300 acres between them. In July 1878 over 300 acres of the Keon estate was offered for sale in the Land Judges' Court by William Keon. The trustees of John Pottinger offered a further 140 acres of land at Keonbrook for sale at the same time. Miles Gerald Keon (1821-1875), the last male descendant of the Keonbrook branch, was a novelist and colonial official. By 1906 the property at Keonbrook including the house and 140 acres of untenanted land was owned by Bridget Mollahan. At the time of Griffith's Valuation William E. Keon held the townland of Annaghmore, parish of Ogulla, barony and county of Roscommon. In the 1870s William McKeon of Strokestown owned 518 acres in county Roscommon.
|Name||Townland||Civil Parish||PLU||DED||Barony||County||Map Ref|
OSI Ref: G994057
OS Sheet: 27
Discovery map: 33
OSI Ref: G988059
OS Sheet: 27
Discovery map: 33
- Papers relating to Roscommon property of W.I Keon, c.1897. Hoey & Denning Collection. Small Accs. Index 99, Parcel 30; National Archives of Ireland
- Sale rental for estate of William Keon in Cos Mayo & Leitrim, 1878. Small Accs. Index 8, E.J. French solicitors papers, LEC 103; National Archives of Ireland
- Solicitors' Papers, include references to a court case Franic Philip Count Magawly v John Brady, Dromgoole and others re lands of Keonbrook, Co Leitrim. Small Accs. Index 11; National Archives of Ireland
- Encumbered Estates’ Court Rentals (O’Brien), Keon, 23 February 1855, Vol 33, MRGS 39/015, (microfilm copy in NUIG); National Archives of Ireland
- Landed Judges’ Court Rentals (O’Brien), Keon, 5 July 1878, Vol 133, MRGS 39/059, (microfilm copy in NUIG); National Archives of Ireland
- Landed Judges’ Court Rentals (O’Brien), Pottinger, 6 July 1878, Vol 133, MRGS 39/059, (microfilm copy in NUIG); National Archives of Ireland
- West Collection includes marriage settlement of John D. Brady & Mary Elinor Keon, 1827, leases of lands in Cos Longford & Leitrim by John Brady, 1831 Magawley v Brady & others, 1848. Small Accessions Index No 82. D.12631V & D.12610-12612, CO 2610; National Archives of Ireland
- Hoey & Dennings, solicitor's collection, includes miscellaneous papers re the estate of W.I. Keon, Co Roscommon, c 1897. Small Accs. Index 99, Parcel 30; National Archives of Ireland
Contemporary printed sources
- PARLIAMENTARY PAPERS. ''Return of owners of land of one acre and upwards, in the several counties .... in Ireland''. HC 1876, LXXX: 304 & 317
- LEWIS, Samuel. ''A Topographical Dictionary of Ireland''. London: S. Lewis & Co., 1837: Vol II, 214.
- ''GRIFFITH'S VALUATION OF IRELAND'[Primary Valuation of Tenements]', 1850-1858. : Carrick-on-Shannon Union, 75
- LEET, Ambrose. ''A directory to the market towns, villages, gentlemen's seats, and other noted places in Ireland''. Dublin: Printed by B. Smith, 1814 : 306
- ''GRIFFITH'S VALUATION OF IRELAND'[Primary Valuation of Tenements]', 1850-1858. : Carrick-on-Shannon Union, 88.
- PARLIAMENTARY PAPERS. ''Return of Untenanted Lands in Rural Districts, Distinguishing Demesnes on Which There is a Mansion...'', HC 1906, c, 177: 345.
- HUSSEY DE BURGH, U. H. ''The Landowners of Ireland. An alphabetical list of the owners of estates of 500 acres or £500 valuation and upwards in Ireland''. Dublin: Hodges, Foster and Figgis, 1878. [available online at www.askaboutireland.ie] : 296
- McPARLAN, James. ''Statistical Survey of the county of Leitrim''. Dublin: Royal Dublin Society, 1802. : 110.
- McPARLAN, James. ''Statistical Survey of the county of Leitrim''. Dublin: Royal Dublin Society, 1802. : 111.
Modern printed sources
- ''Notes and Queries''. : REYNOLDS, Henry Fitzgerald. Irish Family History, Keon of Moreagh and Keonbrook, Co Leitrim. VII (1920), 1-4, 25-26, 65-67
- MATTHEW, H.C.G. and HARRISON, Brian (eds). ''Oxford Dictionary of National Biography''. Oxford: University Press, 2004: XXXI, 358