Thomas Stratford Dennis of Fortgranite, Baltinglass, county Wicklow, owned over 3500 acres in county Kerry in the 1870s. Burke states that this branch of the Dennis family were descended from the Swifte family of Swiftesheath, county Kilkenny and Lynn, county Westmeath. In the 1780s, Rev. Meade Swifte succeeded to the county Kerry estates of his maternal uncle James Dennis, Lord Tracton, of Tracton Abbey, county Cork and adopted the surname Dennis. He held several townlands in the parish of Killehenny, barony of Iraghticonnor at the time of Griffith's Valuation. John Dennis was the lessor of several townlands in the parish of Murcher in the same barony at that time.
Contemporary printed sources
- PARLIAMENTARY PAPERS. ''Return of owners of land of one acre and upwards, in the several counties .... in Ireland''. HC 1876, LXXX: 142
- 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] : 123
- ''GRIFFITH'S VALUATION OF IRELAND'[Primary Valuation of Tenements]', 1850-1858. : Clanmaurice Barony: 122 (Billeragh)