Jacqueline Kennedy’s previously unseen letters to British diplomat David Ormsby Gore turning down his marriage proposal will be offered at Bonhams later this month.

The collection was discovered during a valuation at Glyn Cywarch, Gore’s ancestral home in Wales.

The collection sheds light on the nature of Kennedy and Gore's relationship

It dates from just after JFK’s assassination in 1963 up until 1968, when Jacqueline turned down Gore down in favour of Greek shipping magnate Aristotle Onassis. 

The remarkable story of their relationship is laid out in the letters. It follows decades of speculation on what really went on between them.

Gore writes in agonised response to Jackie’s rejection of his offer of marriage: “I have tried for hours and hours to understand your explanation and I suppose I do in a way, without agreeing with it; but what I find unbearable and in a way, dearest Jackie, untrue is that you could come to such a categorical conclusion…”

She responds: “We have known so much & shared & lost so much together – Even if it isn’t the way you wish now – I hope that bond of love and pain will never be cut… You are like my beloved beloved brother – and mentor – and the only original spirit I know – as you were to Jack.”

In other letters Jacqueline writes movingly of the pain of losing JFK. 

Matthew Haley, Bonhams’ head of books and manuscripts, said: “For decades, biographers have speculated on the precise relationship between Jackie Kennedy and David Ormsby Gore.

“These letters now show without doubt how close they came to marriage and why Jackie decided to marry Onassis instead.

“The correspondence has been sitting in two official red Government despatch boxes for more than 40 years.

“The keys were nowhere to be found and in the end we had to call a locksmith to slice through the locks. It was one of those astonishing moments when you can’t quite believe what you’re seeing.”

The lot is expected to sell for around £100,000-150,000 ($125,000-$187,500) when it crosses the block in London as part of an auction titled “The Contents of Glyn Cywarch – the Property of Lord Harlech Sale”.  

We have an original poster from JFK's 1960 presidential campaign for sale. 

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