The Beggs were resident in the parish of Aughrim, barony and county of Roscommon, in the mid 18th century and living at Beech Abbey by the end of the century. The estate of Margaret Begg, a minor, in the parish of Aughrim, barony and county of Roscommon, was adverted for sale in April 1851 along with the mansion house and demesne of Mount Dalton, barony of Rathconrath, county Westmeath. The county Roscommon lands appear to have been purchased by Thomas Babington. Oliver William Costello Begg of Mount Dalton appears in the list of subscribers to Samuel Lewis ''Topographical Dictionary of Ireland'' (1837). At the time of Griffith's Valuation, Terroll and John Begg held the townland of Kye, parish of Clooncraff, barony of Roscommon. Kye was held on a lease dated 12 Oct 1785 from Patrick Dillon to James Begg and was advertised for sale in February 1854. Tyrrell Begg was the tenant. In the 1870s Tyrrell Begg and other Begg family members of Elphin owned 352 acres in county Roscommon.
- Encumbered Estates’ Court Rentals (O’Brien), Begg, 25 Apr 1851, Vol 6, MRGS 39/003, (microfilm copy in NUIG); National Archives of Ireland
- Encumbered Estates’ Court Rentals (O’Brien), Dillon, 17 Feb 1854, Vol 26, MRGS 39/011, (microfilm copy in NUIG); National Archives of Ireland
Contemporary printed sources
- LEWIS, Samuel. ''A Topographical Dictionary of Ireland''. London: S. Lewis & Co., 1837: Vol I, xi
- PARLIAMENTARY PAPERS. ''Return of owners of land of one acre and upwards, in the several counties .... in Ireland''. HC 1876, LXXX: 314
- ORDNANCE SURVEY NAME BOOKS, County Roscommon: Vol I, 57
- LEGG, Marie Louise (ed). ''Census of Elphin 1749''. Dublin: Irish Manuscripts Commission, 2004: 46