Circa 26 March 1724 Lord Walpole married the 15-year-old heiress
Margaret Rolle (1709–1781), the only surviving daughter of Colonel Samuel Rolle (1646–1719), of
Heanton Satchville, Petrockstowe. Margaret was the heiress to a junior branch of the great Rolle family of
Stevenstone in Devon and to her paternal grandmother, born Lady Arabella Clinton, an aunt and co-heiress of her nephew
Edward Clinton, 5th Earl of Lincoln and 13th Baron Clinton (d. 1692). The marriage was not a success and Lady Walpole quarrelled violently with his whole family. After one son was born they lived apart and later obtained a legal separation. In 1736
Hannah Norsa, a leading singer and actress at
Covent Garden, moved to
Houghton Hall in Norfolk and remained there as Walpole's mistress until his death in March 1751. Her financial support may have saved him from dying bankrupt. In Walpole's many absences Hannah Norsa was escorted in her
landau and six horses by his chaplain, Rev William Paxton, who received the position as a small part of the Walpole family compensation for
his father's defence of Walpole's father, the Prime Minister. His estranged widow became the
15th Baroness Clinton succeeding in her own right after the death of her cousin
Hugh Fortescue, 1st Earl Clinton. She had remarried on Walpole's death but soon separated from her second husband,
Hon Sewallis Shirley, a son of the
1st Earl Ferrers and Comptroller of
Queen Charlotte's Household. Lady Clinton died at Pisa, in Tuscany, in 1781, and was buried at Leghorn, "a woman of very singular character and considered half mad" (according to her friend,
Selina, Countess of Huntingdon). Walpole himself is buried in the
Church of St Martin at Tours on the
Houghton Hall estate. ==Progeny==