Biography of Thomas Osborne 4th Duke Leeds 1713-1789
Paternal Family Tree: Osborne
On 16 Dec 1712 [his father] Peregrine Osborne 3rd Duke Leeds (age 21) and [his step-mother] Elizabeth Harley (age 23) were married. She the daughter of Robert Harley 1st Earl of Oxford and Earl Mortimer (age 51) and Elizabeth Foley Countess of Oxford and Mortimer. He the son of Peregrine Osborne 2nd Duke Leeds (age 53) and Bridget Hyde Duchess Leeds (age 50).
On 06 Nov 1713 Thomas Osborne 4th Duke Leeds was born to Peregrine Osborne 3rd Duke Leeds (age 21).
On 17 Sep 1719 [his father] Peregrine Osborne 3rd Duke Leeds (age 27) and [his step-mother] Anne Seymour Duchess Leeds (age 10) were married. She the daughter of Charles Seymour 6th Duke Somerset (age 57) and Elizabeth Percy Duchess Somerset (age 52). He the son of Peregrine Osborne 2nd Duke Leeds (age 60) and Bridget Hyde Duchess Leeds (age 57).
Around 1725 Thomas Osborne 4th Duke Leeds (age 11) educated at Westminster School [Map].
In 1729 Thomas Osborne 4th Duke Leeds (age 15) was elected Fellow of the Royal Society.
On 25 Jun 1729 [his grandfather] Peregrine Osborne 2nd Duke Leeds (age 70) died. His son [his father] Peregrine Osborne 3rd Duke Leeds (age 37) succeeded 3rd Duke Leeds, 3rd Earl of Danby, 3rd Viscount Osborne, 3rd Viscount Latimer, 3rd Baron Osborne of Kinderton, 4th Baronet Osborne of Kiveton. [his step-mother] Anne Seymour Duchess Leeds by marriage Duchess Leeds.
In 1731 Thomas Osborne 4th Duke Leeds (age 17) was educated at Christ Church College, Oxford University.
On 09 May 1731 [his father] Peregrine Osborne 3rd Duke Leeds (age 39) died. His son Thomas Osborne 4th Duke Leeds (age 17) succeeded 4th Duke Leeds, 4th Earl of Danby, 4th Viscount Osborne, 4th Viscount Latimer, 4th Baron Osborne of Kinderton, 5th Baronet Osborne of Kiveton.
In 1738 Thomas Osborne 4th Duke Leeds (age 24) was awarded Doctor of Civil Law at Christ Church College, Oxford University.
On 26 Jun 1740 Thomas Osborne 4th Duke Leeds (age 26) and Mary Godolphin Duchess Leeds were married. She by marriage Duchess Leeds. She the daughter of Francis Godolphin 2nd Earl Godolphin (age 61) and Henrietta Churchill 2nd Duchess Marlborough. He the son of Peregrine Osborne 3rd Duke Leeds.
In 1749 King George II of Great Britain and Ireland (age 65) created new Garter Knights as follows:
560th Johann Adolph Wettin Duke Saxe Weissenfels,
561st King George III of Great Britain and Ireland (age 10),
562nd Charles William Frederick "The Wild Margrave" Hohenzollern (age 36),
563rd Thomas Osborne 4th Duke Leeds (age 35),
564th John Russell 4th Duke Bedford (age 38),
565th William Anne Keppel 2nd Earl Albermarle (age 46),
566th John Carteret 2nd Earl Granville (age 58).
On 29 Jan 1751 [his son] Francis Osborne 5th Duke Leeds was born to Thomas Osborne 4th Duke Leeds (age 37) and [his wife] Mary Godolphin Duchess Leeds.
In 1757 Thomas Osborne 4th Duke Leeds (age 43) was appointed Privy Council.
In 1764 [his wife] Mary Godolphin Duchess Leeds died.
On 29 Nov 1773 [his son] Francis Osborne 5th Duke Leeds (age 22) and [his daughter-in-law] Amelia Darcy 12th Baroness Darcy 9th Baroness Conyers (age 19) were married. She the daughter of Robert Darcy 4th Earl Holderness (age 55). He the son of Thomas Osborne 4th Duke Leeds (age 60) and Mary Godolphin Duchess Leeds. She a great x 4 granddaughter of King James I of England and Ireland and VI of Scotland. 
In 1788 [his son] Francis Osborne 5th Duke Leeds (age 36) and [his daughter-in-law] Catherine Anguish Duchess Leeds (age 23) were married. He the son of Thomas Osborne 4th Duke Leeds (age 74) and Mary Godolphin Duchess Leeds.
On 23 Mar 1789 Thomas Osborne 4th Duke Leeds (age 75) died at St James' Square. He was buried at the Osborne Family Chapel at All Hallows' Church Harthill [Map]. His son [his son] Francis Osborne 5th Duke Leeds (age 38) succeeded 5th Duke Leeds, 5th Earl of Danby, 5th Viscount Osborne, 5th Viscount Latimer, 5th Baron Osborne of Kinderton, 6th Baronet Osborne of Kiveton. [his daughter-in-law] Catherine Anguish Duchess Leeds (age 25) by marriage Duchess Leeds.
Kings Wessex: Great x 21 Grand Son of King Edmund "Ironside" I of England
Kings Gwynedd: Great x 19 Grand Son of Owain "Great" King Gwynedd
Kings Seisyllwg: Great x 24 Grand Son of Hywel "Dda aka Good" King Seisyllwg King Deheubarth
Kings Powys: Great x 20 Grand Son of Maredudd ap Bleddyn King Powys
Kings England: Great x 12 Grand Son of King Edward III of England
Kings Scotland: Great x 16 Grand Son of William "Lion" I King Scotland
Kings Franks: Great x 17 Grand Son of Louis VII King Franks
Kings France: Great x 14 Grand Son of Philip "The Fair" IV King France
Great x 4 Grandfather: Edward Osborne
Great x 3 Grandfather: Hewett Osborne
Great x 4 Grandmother: Anne Hewett
Great x 2 Grandfather: Edward Osborne 1st Baronet
Great x 4 Grandfather: Thomas Fleetwood
Great x 3 Grandmother: Joyce Fleetwood
Great x 4 Grandmother: Bridget Spring
Great x 1 Grandfather: Thomas Osborne 1st Duke Leeds 9 x Great Grand Son of King Edward III of England
Great x 3 Grandfather: Thomas Walmesley
Great x 2 Grandmother: Anne Walmesley Lady Osborne 8 x Great Grand Daughter of King Edward III of England
Great x 4 Grandfather: John Danvers
Great x 3 Grandmother: Eleanor Danvers 7 x Great Grand Daughter of King Edward III of England
Great x 4 Grandmother: Elizabeth Neville
6 x Great Grand Daughter of King Edward III of England
GrandFather: Peregrine Osborne 2nd Duke Leeds 10 x Great Grand Son of King Edward III of England
Great x 4 Grandfather: Peregrine Bertie 13th Baron Willoughby
9 x Great Grand Son of King Henry III of England
Great x 3 Grandfather: Robert Bertie 1st Earl Lindsey 8 x Great Grand Son of King Edward "Longshanks" I of England
Great x 4 Grandmother: Mary Vere Baroness Willoughby Eresby
7 x Great Grand Daughter of King Edward "Longshanks" I of England
Great x 2 Grandfather: Montagu Bertie 2nd Earl Lindsey 9 x Great Grand Son of King Edward "Longshanks" I of England
Great x 4 Grandfather: Edward Montagu 1st Baron Montagu
9 x Great Grand Son of King Edward "Longshanks" I of England
Great x 3 Grandmother: Elizabeth Montagu Countess Lindsey 10 x Great Grand Daughter of King Edward "Longshanks" I of England
Great x 4 Grandmother: Elizabeth Jeffrey
Great x 1 Grandmother: Bridget Bertie Duchess Leeds 10 x Great Grand Daughter of King Edward "Longshanks" I of England
Great x 4 Grandfather: William Cockayne
Great x 3 Grandfather: William Cockayne
Great x 4 Grandmother: Elizabeth Medcalf
Great x 2 Grandmother: Martha Cockayne Countess Lindsey and Holderness
Great x 4 Grandfather: Richard Morris
Great x 3 Grandmother: Mary Morris Countess Dover
Father: Peregrine Osborne 3rd Duke Leeds 11 x Great Grand Son of King Edward III of England
Great x 2 Grandfather: Nicholas Hyde 1st Baronet
Great x 1 Grandfather: Thomas Hyde 2nd Baronet
GrandMother: Bridget Hyde Duchess Leeds
Thomas Osborne 4th Duke Leeds 12 x Great Grand Son of King Edward III of England