Catherine Conduitt / Montagu

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Catherine Conduitt / Montagu (Barton)

Birthdate: (60)
Death: 1739 (60)
Place of Burial: London, Greater London, United Kingdom
Immediate Family:

Daughter of Rev. Robert Barton and Hannah Barton
Wife of John Conduitt
Partner of Charles Montagu, 1st Earl of Halifax
Mother of Catherine Wallop
Sister of Margaret Barton and Robert Barton
Half sister of Barbara Lisle

Managed by: Lorna Felicity Isaac
Last Updated:

About Catherine Conduitt / Montagu

Catherine Barton (1679–1739) was Isaac Newton's half-niece, probable mistress of Charles Montague and later, the wife of John Conduitt.

Early life

She was the second daughter of Robert Barton and his second wife, Hannah Smith, half-niece of Isaac Newton, and baptized at Brigstock, Northampton on 25 Nov 1679.

She was remarked upon by several men to be beautiful, witty and clever. Sometime after her uncle Isaac moved to London to become Warden of the Mint in April 1696 she moved there to live with him. She was known as a brilliant conversationalist, and attracted the admiration of such famous figures as Jonathan Swift and Voltaire. Her uncle Isaac was also fond of her; an excerpt of an uncharacteristically warm letter from Newton survives, regarding her contraction of smallpox: "Pray let me know by your next how your face is and if your fevour [sic] be going. Perhaps warm milk from ye Cow may help to abate it. I am Your loving Unkle (sic), Is. Newton."[4]

Voltaire insinuated that Newton's preferment to the Royal Mint was the result of her alleged affair with Charles Montague. However, although it is true that Isaac was appointed under the patronage of Charles Montague, it is clear that Catherine Barton came up to London and met Montague after the appointment, not before.

Relationship to Charles Montague

Following the death of Charles Montague's wife in 1698, Barton became his housekeeper and probably his mistress.[citation needed] There was much contemporary gossip on the subject, and thinly disguised accusations appeared in print. Delariviere Manley's Memoirs of 1710 featured a character called Bartica who was widely taken to represent Barton.

Montague, by then Earl of Halifax, died of an inflammation of the lungs in May, 1715.

His will contained two codicils: the first dated 12 April 1706, left the sum of £3000 and all his jewels to Barton; a second dated 1 February 1713 left her an additional £5000 plus his interest in the rangership of Bushey Park and his manor of Apscourt in Surrey to pay for the repairs to Bushey Lodge. On 30 August, however, he revokes the first codicil and begs his executor, his nephew George Montague, not to make a dispute over her legacies. Montague wrote that these bequests were "as a token of the sincere love, affection and esteem, I have long had for her person, and as a small recompense for the pleasure and happiness I have had in her conversation."


Barton then returned to live with her uncle at his home in St Martin's Street.[citation needed] On 9 July 1717 she became engaged to marry John Conduitt who had only set foot in England a few weeks earlier in May of that year. On 23 August they were issued a licence to marry at St Paul's Covent Garden, but actually married three days later at St Martin in the Fields.[7] The couple had one daughter, Catherine, born in 1721.

Later life

The couple lived at Cranbury Park, near Winchester; towards the end of his life, Sir Isaac Newton took up residence at Cranbury with his niece and her husband until his death in 1727.

Her husband John Conduitt died on 23 May 1737; she died in 1739 and was buried with her uncle and husband in Westminster Abbey. Their only daughter and heir Catherine married John Wallop, Viscount Lymington, the eldest son of the first Earl of Portsmouth, and their son, John Wallop, succeeded as second Earl of Portsmouth.

Barton, Catherine 1679-1739 Daughter of Newton's half sister Hannah Smith. She moved to London before 1700 to become Newton's housekeeper. Between 1700 and 1715 Catherine may have been the mistress of Charles Montague, first Earl of Halifax and Newton's patron. She married John Conduitt in 1717.

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Catherine Conduitt / Montagu's Timeline

Age 42
Age 60
London, Greater London, United Kingdom