Sir Tatton Sykes, 5th Baronet
Sir Tatton Sykes, 5th Baronet( 13 March 1826 – 4 May 1913) was an English landowner, racehorse breeder, church- builder and eccentric.
He was the elder son of Sir Tatton Sykes, 4th Baronet and Mary Ann Foulis, and succeeded to the Sykes baronetcy on his father's death in 1863.
His brother was the Conservative MP Christopher Sykes.
On 3 August 1874, at the age of 48, he married Christina Anne Jessica Cavendish- Bentinck, daughter of George Augustus Frederick Cavendish- Bentinck and Prudentia Penelope Leslie.
His wife was 30 years younger than him and it was not a happy marriage.
The couple eventually separated, with Sir Tatton disowning his wife's future debts.
Sykes died in May 1913 at age 87, and was succeeded in the baronetcy by his son Mark.
William Cavendish-Bentinck, 3rd Duke of Portland
William Henry Cavendish Cavendish-Bentinck, 3rd Duke of Portland, (14 April 1738 – 30 October 1809) was a British Whig and Tory politician during the late Georgian era.
He served as Chancellor of the University of Oxford (1792–1809) and twice as the Prime Minister, of Great Britain (1783) and then of the United Kingdom (1807–09).
The twenty-four years between his two terms as Prime Minister is the longest gap between terms of office of any British Prime Minister.
Portland was known before 1762 by the courtesy title Marquess of Titchfield.
He held a title of every degree of British nobility: Duke, Marquess, Earl, Viscount, and Baron.
He is also a great-great-great-grandfather of Elizabeth II through her maternal grandmother.
Elizabeth Livingston Cavendish-Bentinck
Elizabeth Livingston Cavendish- Bentinck( August 12, 1855 – November 4, 1943), was an American born member of the Livingston family who married a British Member of Parliament from the Cavendish- Bentinck family and was a prominent member of New York Society during the Gilded Age.
William Cavendish-Bentinck, 6th Duke of Portland
William John Arthur Charles James Cavendish- Bentinck, 6th Duke of Portland,( 28 December 1857 – 26 April 1943), known as William Cavendish- Bentinck until 1879, was a British landowner, courtier, and Conservative politician.
He notably served as Master of the Horse between 1886 and 1892 and again between 1895 and 1905.
Charles Cavendish-Bentinck (priest)
Charles William Frederick Cavendish-Bentinck (8 November 1817 – 17 August 1865) was a clergyman of the Church of England, holding livings in Bedfordshire, and a great-grandfather of Queen Elizabeth II.
He used his names in the order William Charles Frederick Cavendish-Bentinck, and his usual signature was "W. C. C. Bentinck".
Victor Cavendish-Bentinck, 9th Duke of Portland
Victor Frederick William Cavendish- Bentinck, 9th Duke of Portland,( 18 June 1897 – 30 July 1990), known as Victor Cavendish- Bentinck until 1980, was a British diplomat, businessman, and peer.
He served as Chairman of the Joint Intelligence Committee during the Second World War and was British Ambassador to Poland between 1945 and 1947.
Ferdinand Cavendish-Bentinck, 8th Duke of Portland
Ferdinand William Cavendish- Bentinck, 8th Duke of Portland( 4 July 1889 – 13 December 1980) was a British peer and grandson of George Cavendish- Bentinck.
The son of Frederick W. Cavendish- Bentinck and Ruth Cavendish- Bentinck, grandson of George Cavendish- Bentinck, and great- grandson of Major General Lord Frederick Cavendish- Bentinck, fourth son of the 3rd Duke of Portland, the young Cavendish- Bentinck was educated at Eton and the Royal Military College, Sandhurst, passing out in 1910.
He was commissioned into the 60th Rifles and was posted to Malta and British India before seeing active service in the European theatre of the First World War, which left him severely wounded.
He then took up a posting as assistant adjutant at the Royal Military College.
After the war, his main sphere of activity was in East Africa, where he served as Private Secretary to the Governor of Uganda( 1925 – 1927), Chairman of the Agricultural Production and Settlement Board for Kenya( 1939 – 1945), Timber Controller for East Africa( 1940 – 1945), Member of the Government of Kenya for Agriculture and Natural Resources( 1945 – 1955), and Speaker of the Kenya Legislative Council( 1955 – 1960).
He was a Delegate to the Delhi Conference of 1940.
He became the heir presumptive of his third cousin, William Cavendish- Bentinck, 7th Duke of Portland, after the deaths of the latter's brother Lord( Francis) Morven Dallas Cavendish- Bentinck( 1900- 1950) and half- uncle Charles Cavendish- Bentinck( 1868- 1956).
The previous duke's lands came to stay with the descendants of the 7th Duke and never passed to the distantly related 8th Duke in 1977.
In the early 20th century the usual" tail male" arrangement of the" entailed" largest landholdings became deprecated by powerful statutes as it tended to leave noble daughters with little.
The 6th Duke, before dying in 1943 broke the entails and set up a trust which saw as his son the future 7th Duke left no son Welbeck Abbey and other large holdings would go to his granddaughters in turn including Lady Anne Cavendish- Bentinck.
No viable family court case could ensue as the fee tail was abolished as a recognised entity in the abstract(" in law") under the Law of Property Act 1925 and any remote, entailed beneficiaries could be disinherited under the Settled Land Acts.
The new Duke of Portland continued to live in Nairobi.
Elizabeth II shares an ancestor, in the 3rd Duke of Portland, through her maternal grandmother Cecilia Cavendish- Bentinck, and is thus a third cousin, once removed, of the 8th Duke of Portland.
Frederick Cavendish Ponsonby
Major General Hon. Sir Frederick Cavendish Ponsonby( 6 July 1783 – 11 January 1837) was an Anglo- Irish military officer.
Lord Henry Cavendish-Bentinck
Lord Henry Cavendish- Bentinck( 28 May 1863 – 6 October 1931), known as Henry Cavendish- Bentinck until 1880, was a British Conservative politician.
Lord Frederick Cavendish-Bentinck
Major-General Lord Frederick Cavendish-Bentinck (2 November 1781 – 10 February 1828) known as Lord Frederick Bentinck was a British soldier and politician.
The youngest child and fourth son of William Cavendish-Bentinck, 3rd Duke of Portland and Lady Dorothy Cavendish, Cavendish-Bentinck attended Westminster School before joining the army.

Question: What nationality is Lord Frederick Cavendish-Bentinck's father?
Answer: Great Britain