Question: Who is James Tuchet, 6Th Earl Of Castlehaven's paternal grandfather?

Knowledge 1: James Tuchet, 6th Earl of Castlehaven
James Tuchet, 6th Earl of Castlehaven (died 12 October 1740) was the son of James Tuchet, 5th Earl of Castlehaven and his wife Anne Pelson.He succeeded his father as Earl of Castlehaven and Baron Audley on 9 August 1700.He married, on 14 May 1722, Elizabeth Arundell (1693–1743), daughter of Henry Arundell, 5th Baron Arundell of Wardour and his wife, née Elizabeth Panton.They had two sons, and at least one daughter:He is buried at the church of St. Sulpice in Paris, France. [SEP] Knowledge 2: James Tuchet, 5th Earl of Castlehaven
James Tuchet, 5th Earl of Castlehaven (died 12 August 1700) was the son of Mervyn Tuchet, 4th Earl of Castlehaven and Mary Talbot.He succeeded his father as Earl of Castlehaven on 2 November 1686.He married Anne Pelson, daughter of Richard Pelson and his wife, née Anne Villiers, daughter of Christopher Villiers, 1st Earl of Anglesey.They had one son, James, who succeeded him as Earl of Castlehaven.He died of apoplexy.His gravestone is in the floor of the south aisle of the retrochoir at Winchester Cathedral.
Knowledge 1: James Tuchet, 6th Earl of Castlehaven
James Tuchet, 6th Earl of Castlehaven (died 12 October 1740) was the son of James Tuchet, 5th Earl of Castlehaven and his wife Anne Pelson.He succeeded his father as Earl of Castlehaven and Baron Audley on 9 August 1700.He married, on 14 May 1722, Elizabeth Arundell (1693–1743), daughter of Henry Arundell, 5th Baron Arundell of Wardour and his wife, née Elizabeth Panton.They had two sons, and at least one daughter:He is buried at the church of St. Sulpice in Paris, France. [SEP] Knowledge 2: George Thicknesse, 19th Baron Audley
George Thicknesse, later Thicknesse-Touchet, 19th Baron Audley (4 February 1758 – 24 August 1818) was an English peer.George Thicknesse-Touchet was the son of Captain Philip Thicknesse and Lady Elizabeth Tuchet, daughter of James Tuchet, 6th Earl of Castlehaven.Upon the deaths of his mother's two brothers, the Earldom became extinct, but the barony passed in the female line.He gained the rank of Ensign in the 2nd (The Queen's Royal) Regiment of Foot.He married, Elizabeth Delaval, daughter of Sir John Hussey Delaval, 1st Baron Delaval of Seaton Delaval and Susannah Robinson, on 21 May 1781 in Hanover Square, Mayfair, London, England.Later he married Augusta Henrietta Catherina Boisdaune, daughter of Rev. André Boisdaune and Elizabeth Strode, on 2 May 1792.Thicknesse-Touchet died in Sandridge Lodge, near Melksham, Wiltshire and was buried in Melksham.He was succeeded by his only son, George Thicknesse-Touchet (1783–1837).
Knowledge 1: James Tuchet, 6th Earl of Castlehaven
James Tuchet, 6th Earl of Castlehaven (died 12 October 1740) was the son of James Tuchet, 5th Earl of Castlehaven and his wife Anne Pelson.He succeeded his father as Earl of Castlehaven and Baron Audley on 9 August 1700.He married, on 14 May 1722, Elizabeth Arundell (1693–1743), daughter of Henry Arundell, 5th Baron Arundell of Wardour and his wife, née Elizabeth Panton.They had two sons, and at least one daughter:He is buried at the church of St. Sulpice in Paris, France. [SEP] Knowledge 2: John Butler (Irish Confederate)
Colonel John Butler was an officer of the Irish Confederate Army of the 1640s during the War of the Three Kingdoms.He was the younger brother of Richard Butler, 3rd Viscount Mountgarret and part of the powerful Butler family of the Munster-Leinster border area.Of Old English descent, like most of the family he was a Roman Catholic.Butler took part in the unsuccessful 1644 Ulster Campaign as part of the Ulster Army under the command of James Tuchet, 3rd Earl of Castlehaven and Owen Roe O'Neill.He was a cousin of James Butler, 1st Duke of Ormonde, the Lord Lieutenant and commander of the Royalist Irish Army.

Answer: Mervyn Tuchet, 4th Earl of Castlehaven