Amelia Osborne, Marchioness of Carmarthen
Amelia Byron, Baroness Conyers, 12th Baroness Darcy de Knayth, 9th Baroness Conyers, 5th Countess of Mértola (née Lady Amelia Darcy; 12 October 1754 – 27 January 1784), known as the Marchioness of Carmarthen from 1773–9, was a British peer and a Portuguese countess. She is best known for eloping with John "Mad Jack" Byron, father of Lord Byron.
Amelia Osborne, Marchioness of Carmarthen

François-Hubert Drouais · Self-photographed · Public domain
- Name
- Amelia Byron, Baroness Conyers
- Birth Name
- Lady Amelia d'Arcy
- Born
- 12 October 1754
- Died
- 27 January 1784
- Place of death
- Mayfair, London
- Nationality
- Kingdom of Great Britain
- Occupation
- poet · writer · aristocrat
- Fields
- poetry
- Languages
- English
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Amelia Byron, Baroness Conyers, 12th Baroness Darcy de Knayth, 9th Baroness Conyers, 5th Countess of Mértola (née Lady Amelia Darcy; 12 October 1754 – 27 January 1784), known as the Marchioness of Carmarthen from 1773–9, was a British peer and a Portuguese countess. She is best known for eloping with John "Mad Jack" Byron, father of Lord Byron.
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Amelia Osborne, Marchioness of Carmarthen was an aristocrat, poet and writer, of British nationality. Activity centred on poetry. Languages used include English.
Composed from admitted, traceable facts · 01 October 2026
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Key facts
Key facts
• Name — Amelia Byron, Baroness Conyers • Birth Name — Lady Amelia d'Arcy • Born — 12 October 1754 • Died — 27 January 1784 • Place of death — Mayfair, London • Parents — The 4th Earl of Holderness Mary Doublet • Children — The 6th Duke of Leeds Mary, Countess of Chichester The 1st Baron Godolphin Hon. Augusta Leigh
Early life
Early life
Lady Amelia was the only surviving child of the 4th Earl of Holderness and his wife, the former Mary Doublet. Her portrait was painted in about 1764 by François-Hubert Drouais.
Marriage to Marquess of Carmarthen
Marriage to Marquess of Carmarthen
On 29 November 1773, Lady Amelia married Francis, Marquess of Carmarthen, in London, and they had three children: • Lord George William Frederick Osborne (21 July 1775 – 10 July 1838), later 6th Duke of Leeds; married Lady Charlotte Townshend, daughter of the 1st Marquess Townshend, on 17 August 1797 and had issue. • Lady Mary Henrietta Juliana Osborne (7 September 1776 – 21 October 1862); married the 2nd Earl of Chichester (28 April 1756 – 4 July 1826) in 1801 and had issue. • Lord Francis Godolphin Osborne (18 October 1777 – 15 February 1850), later 1st Baron Godolphin; married The Hon. Elizabeth Eden, third daughter of the 1st Baron Auckland, on 31 March 1800 and had issue. In early 1777, Lady Amelia's mother, Lady Holderness, broke off relations with her daughter after the Carmarthens gave shelter to Richard Glover (son of the poet), a friend of Lord Carmarthen, when he eloped with one of the daughters of Solomon Dayrolles. • Illustration — Portrait of the Duke of Leeds by Thomas Lawrence. Her marriage to her first husband ended when she eloped with Captain Jack Byron On 16 May 1778, as the only surviving child of her father, Lady Amelia succeeded de jure to the titles of 12th Baroness Darcy de Knayth and 9th Baroness Conyers in her own right, and to the Portuguese countship of Mértola. Her right to the baronies of Darcy de Knayth and Conyers was eventually confirmed in 1798, long after her death.
Affair with "Mad Jack" Byron
Affair with "Mad Jack" Byron
In December 1778, Lady Carmarthen's marriage ended when she ran off with Captain John "Mad Jack" Byron. The previous month, Byron visited her at home in Grosvenor Square when her husband was absent, and they began an affair. Lord and Lady Carmarthen were divorced on 31 May 1779. Almost immediately after the divorce, Lady Conyers, as she was styled, married Byron. They had three children: • Hon. Sophia Georgina Byron (18 July 1779 – died aged two months; buried at Twickenham on 18 September 1779). • Unnamed son (died at birth, ca. 1780/81). • Hon. Augusta Maria Byron (26 January 1783 – 12 October 1851).
Death
Death
A year after the birth of the last child, Lady Conyers died following a lingering illness at her home at Upper Brook Street, Mayfair. Her titles were inherited by her eldest son, George. By his second wife, her widower became the father of the poet, Lord Byron.
Identity and origins
Identity and origins
Her recorded language was English. She was the child of Robert Darcy, 4th Earl of Holderness and Mary Darcy, Countess of Holderness. She married Francis Osborne, 5th Duke of Leeds and John Byron. 4 children are recorded: Augusta Leigh, Francis Osborne, 1st Baron Godolphin, George Osborne, 6th Duke of Leeds and Mary Pelham, Countess of Chichester.
Life and career
Dated record
Life and career
The full dated record · 2 entries
1754
Amelia Osborne, Marchioness of Carmarthen born.
1784
Amelia Osborne, Marchioness of Carmarthen died.
Notes from the source article
Cited by Wikipedia
Notes from the source article
These works are cited by the source article, in its own numbering. They are recorded as its citations, not as sources VALÉORINE has verified.
- 1.Portrait of Lady Amelia Darcy. artnet.
- 2.L. G. Pine, The New Extinct Peerage 1884-1971: Containing Extinct, Abeyant, Dormant and Suspended Peerages With Genealogies and Arms (London, U.K.: Heraldry Today, 1972), page 174.
- 3.Horace Walpole to William Mason, 27 February 1777. W. P. Courtney was unable to identify which of Dayrolles' three daughters was the fugitive for his article in the Dictionary of National Biography.
- 4.Lawbook Exchange Ltd. Trials for Adultery, Or, The History of Divorces. The Lawbook Exchange, Ltd. 10. 1779. 978-1-58477-468-6.
- 5.George Gordon Byron Baron Byron. Byron's Letters and Journals: A New Selection. Oxford University Press. 2015. 978-0-19-872255-7.
- 6.Osborne, Francis, fifth duke of Leeds.
- 7.Births. The Scots Magazine. 55. 5 July 1779.
- 8.Emily Brand. The Fall of the House of Byron: Scandal and Seduction in Georgian England. John Murray. 189, 200. 2020. 9781473664302.
- 9.On Monday night died. Coventry Standard. 2. 2 February 1784.
- 10.Oxford University Press. The Oxford Handbook of Lord Byron. 27-28. 4 October 2024. 978-0-19-253633-4.
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Amelia Osborne, Marchioness of Carmarthen is recorded as poet, writer and aristocrat.
The Encyclopedia exists whether or not anything is for sale. Corrections are recorded rather than overwritten, and every version of this record is kept. Published 17 August 2026.
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