His grandfather was Sir Richard St George. His father was Sir George St George of Carrickdrumrusk and was ancestor of the Barons St George. His two brothers were Oliver and George. Richard was ancestor of the St Georges of Woodsgift in County Kilkenny. The St Georges were orinally from Cambridgeshire who were granted lands in the Headford area by the Cromwellian Commissioners in 1666, much of it formerly held by the Catholic Skerrett family. Their ownership of lands was extensive in the counties of Galway, Roscommon, Limerick and Queen's county (county Laois) confirmed by a patent dated 26 October 1666. The family bore a coat of arms blazoned Argent a Chief Azure overall a Lion rampant Gules crowned Or. Gallowshill in Carrick-on-Shannon, Hatley Manor and Holywell are the ancestral family m