Mary Bowes, Countess of Strathmore and Kinghorne
Mary Eleanor Bowes, Countess of Strathmore and Kinghorne (24 February 1749 – 28 April 1800), known as "The Unhappy Countess", was an 18th-century British heiress, notorious for her licentious lifestyle, who was married at one time to the 9th Earl of Strathmore and Kinghorne.
She and the Earl are ancestors of Queen Elizabeth II.
James Lyon, 7th Earl of Strathmore and Kinghorne
James Lyon, 7th Earl of Strathmore( circa 1702 – 1735) was a Scottish peer and freemason.
He was the son of John Lyon, 4th Earl of Strathmore and Kinghorne and Lady Elizabeth Stanhope.
He was christened on 24 December 1702.
He succeeded as Earl of Strathmore following the stabbing of Charles Lyon, 6th Earl of Strathmore and Kinghorne in a drunken altercation in 1728.
On 6 March 1731 he married Mary Oliphant, daughter of Charles Oliphant( brother of William Oliphant, 11th Lord Oliphant).
He died without issue on 4 January 1735 at Edinburgh, Scotland.
He was succeeded as earl by his younger brother, Thomas Lyon, 8th Earl of Strathmore and Kinghorne, ancestor of Elizabeth Bowes – Lyon, the Queen Mother.
John Bowes, 10th Earl of Strathmore and Kinghorne
John Bowes, 10th Earl of Strathmore and Kinghorne (14 April 1769 – 3 July 1820) was a Scottish nobleman and peer.
He was the eldest son of John Bowes, 9th Earl of Strathmore and Kinghorne and Mary Bowes, Countess of Strathmore and Kinghorne.
His mother was the author of the verse drama, "The Siege of Jerusalem" (1769).
He succeeded his father as Earl of Strathmore and Kinghorne when the latter died at sea on 7 March 1776.
From 30 June 1796 to 24 October 1806 and again from 9 June 1807 to 29 September 1812, he sat as a Scottish Representative peer in the House of Lords.
He had a long affair with the commoner Mary Milner, the beautiful daughter of a gardener; according to some versions (notably offered by Augustus Hare)
he went through a false ceremony of marriage with her.
They had one son:
The Earl was created Baron Bowes in 1815 and held this as a subsidiary title to his death.
He married Mary on 2 July 1820, a mere day before his death.
He attempted to legitimize his son by this marriage and his will named his son as his heir.
According to his will (dated 3 July 1817), all his real estate were left to Mary and five other trustees in name of his son.
The trustees were also required to pay Mary £l,000
p.a for life.
But this deathbed marriage did not prevent his primary title from being inherited by his younger brother Thomas Lyon-Bowes, 11th Earl of Strathmore and Kinghorne.
The Scottish courts agreed that by marrying Mary, John had been legitimized under Scottish law, but since both parties (notably the father) were domiciled in England, English law would prevail.
And Scottish law required Scottish domicile of the parents for the son to have been legitimated.
It was on the point of domicile that John's legitimation failed.
A bitter court case followed over the terms of the Earl's will, and after five years, it was decided that the Earl's son John would inherit his English estates, including Gibside, Streatlam Castle and St Paul's Walden Bury, while his brother would inherit the Scottish estates.
His secondary title as Baron Bowes became extinct.
Mary, now Dowager Countess of Strathmore, married in 1831 her son's tutor William Hutt, and died in 1860.
Her son John Bowes married twice, but had no issue.
He is best known today as the founder of the Bowes Museum.
On his death, all his wealth and properties were inherited by the family of his uncle, reuniting the Scottish and English estates of the Bowes-Lyon family.
John Bowes-Lyon
The Hon. John Herbert" Jock" Bowes- Lyon( 1 April 1886 – 7 February 1930), was the second son of the 14th Earl of Strathmore and Kinghorne and the Countess of Strathmore and Kinghorne, and the brother of Elizabeth Bowes- Lyon( the future Queen Elizabeth and later the Queen Mother).
He was an uncle to Queen Elizabeth II, although he died when she was a small child.
Susan Lyon, Countess of Strathmore and Kinghorne
Susan Lyon, Countess of Strathmore and Kinghorne(" née" Cochrane, – 23 June 1754) was a Scottish noble.
She was the daughter of John Cochrane, 4th Earl of Dundonald, wife of Charles Lyon, 6th Earl of Strathmore and Kinghorne, and" Scotland's fairest daughter", to quote a chronicler of the time.
She married Charles Lyon, 6th Earl of Strathmore and Kinghorne, but he was killed in an unfortunate brawl at Forfar by Carnegie of Finhavon in May 1728, leaving no heir.
The resulting trial is famous for establishing in Scots law the" not guilty" verdict.
Later the Countess married her servant and was shunned by her family until she died in Paris leaving a daughter who was left penniless by her rich relatives.
John Lyon, 4th Earl of Strathmore and Kinghorne
John Lyon, 4th Earl of Strathmore and Kinghorne( 1663 – 1712) was a Scottish nobleman and peer.
He was the son of Patrick Lyon, 3rd Earl of Strathmore and Kinghorne.
He married Elizabeth Stanhope on 21 September 1691 and was succeeded as Earl by his son John Lyon, 5th Earl of Strathmore and Kinghorne.
Thomas Lyon-Bowes, 11th Earl of Strathmore and Kinghorne
Thomas Lyon-Bowes, 11th Earl of Strathmore and Kinghorne( 3 May 1773 – 27 August 1846) was a Scottish nobleman and peer.
He was the third son of John Bowes, 9th Earl of Strathmore and Kinghorne, and Mary Bowes, Countess of Strathmore and Kinghorne.
His mother was the author of the verse drama," The Siege of Jerusalem"( 1769).
He is the great- great- grandfather of Queen Elizabeth The Queen Mother.
The eldest brother was John Bowes, 10th Earl of Strathmore and Kinghorne, who had a long affair with Mary Millner.
Their only son John Bowes was only legitimized following the demise of his father.
He inherited most of the real estate of his father, but none of his titles.
The second brother was George Bowes- Lyon who had married Mary Thornhill, but died childless on 26 December 1806.
Thomas was their only legitimate heir and became the new Earl of Strathmore and Kinghorne on 3 July 1820.
On 25 March 1800, Thomas married firstly Mary Elizabeth Louisa Rodney Carpenter( 1 January 1783 – 1 June 1811), daughter of George Carpenter( 21 October 1713 – 10 November 1782) and his wife Mary Elizabeth Walsh( bap. 18 May 1758, d. 27 November 1812).
They had two children:
His first wife died on 1 June 1811.
He married secondly Eliza Northcote, daughter to a Colonel of the British Army.
They had a daughter:
On 8 December 1817, Thomas married his third wife Marianna Cheape, daughter of John Cheape.
This marriage was childless but lasted until his death.
He was succeeded by his grandson Thomas Lyon-Bowes, 12th Earl of Strathmore and Kinghorne.
Charles Lyon, 6th Earl of Strathmore and Kinghorne
Charles Lyon, 6th Earl of Strathmore and Kinghorne( c. 1699 – 11 May 1728) was a Scottish peer and nobleman.
He was the son of John Lyon, 4th Earl of Strathmore and Kinghorne.
His exact date of birth is unknown but he was baptised on 12 July 1699.
Although his brother John Lyon, 5th Earl of Strathmore and Kinghorne was to display the family ’s royalist sympathies when he joined the Jacobite cause, and was slain at the battle of Sheriffmuir in 1715, Charles, the 6th Earl was not directly implicated in the rebellion and although both his family seats were visited by the Old Pretender( James).
On 25 July 1725 he married Lady Susan Cochrane( died 23 June 1754), daughter of John Cochrane, 4th Earl of Dundonald.
Earl Charles was killed in a brawl at Forfar by Carnegie of Finhaven in May 1728 and left no heir.
John Lyon, 5th Earl of Strathmore and Kinghorne
John Lyon, 5th Earl of Strathmore and Kinghorne( 1696 – 13 November 1715) was a Scottish peer and nobleman.
He was the son of John Lyon, 4th Earl of Strathmore and Kinghorne.
He died fighting with the Jacobites in The Battle of Sheriffmuir in 1715.
Michael Bowes-Lyon, 17th Earl of Strathmore and Kinghorne
Fergus Michael Claude Bowes- Lyon, 17th and 4th Earl of Strathmore and Kinghorne( 31 December 1928 – 19 August 1987), was a British nobleman and peer.
He was a nephew of Queen Elizabeth The Queen Mother( born Elizabeth Bowes- Lyon), and a first cousin of Queen Elizabeth II and Princess Margaret.
He was the son of Capt. The Hon. Michael Claude Hamilton Bowes- Lyon and Elizabeth Margaret Cator.
His paternal grandparents were Claude Bowes- Lyon, 14th Earl of Strathmore and Kinghorne and Cecilia Cavendish- Bentinck.
He married Mary Pamela McCorquodale( b.1932) on 10 April 1956.
They had three children:
He inherited the earldom of Strathmore and Kinghorne upon the death of his first cousin Timothy Bowes- Lyon, 16th Earl of Strathmore and Kinghorne.
He was succeeded by his son.

Question: What is the date of death of John Bowes, 10Th Earl Of Strathmore And Kinghorne's mother?
Answer: 28 April 1800