GRENDON-UNDERWOOD, in the hundred of Ashendon and deanery of Waddesdon, lies about eight miles from Aylesbury, near the road to Bicester. The manor was anciently in the baronial family of St. Amand, who had a seat here, and continued possessed of the estate for several generations. Almeric de St. Amand, of Grendon, was one of the god-fathers of King Edward I. About the year 1795, the manor of Grendon was sold by William Pigott esq. of Dodershall, in the neighbouring parish of Quainton, whose family had possessed it nearly three centuries, to the present proprietor, the Rev. G.H. Jervoise Purefoy, of Shalleston, in this county. In the parish church are monuments of several of the Pigott family; Richard Viscount Say and Sele, who died in 1781, and his lady, Christabella, who died in 1789, at the great age of 94. This lady, who was remarkable for preserving all the vivacity of youth, and joining in the amusements of the young till almost the latest period of her life, resided at Dodershall, which she possessed by jointure from her second husband, John Pigott esq. She was the last of the ancient family of the Tyrells of this county, being daughter of Sir Thomas Tyrell bart by whose death the title became extinct.
Mr. Pigott is patron of the rectory. The parish has been inclosed by an act of Parliament, which passed in the year 1769, when an allotment of land was assigned to the rector, in lieu of tithes, but not to affect his right to tithes of the Woodlands.
Anne, Lady Pigott, founded a charity-school at this place for six children.