Letters from Lord Byron, Elizabeth I and Benjamin Franklin among collection discovered in British stately home

Baron Edmond de Rothschild was one of Europe’s richest and best connected men. But his lifelong hobby – hunting the autographs of the famous – was more akin to that of an idolising youngster.

Nine decades after his death, more than 220 letters he collected over 60 years have just been discovered at Waddesdon Manor, the former Rothschild home, now owned by the National Trust.

The list includes Queen Elizabeth I, Nelson, Byron, Benjamin Franklin, Victor Hugo, Peter Paul Rubens and Madame de Pompadour, plus a few signed documents, including a music manuscript by Mozart and an invoice of his rival, Salieri. “This is a really fascinating discovery,” said Pom Harrington, managing director of the rare books and manuscripts company Peter Harrington. “He clearly delighted in the signatures and letters of some of the most important people in the world.”

But why did a man, himself famous and from Europe’s wealthiest family, want to collect them? Rothschild briefly explained his hobby in an unpublished 1931 memoir, written in French three years before his death: “As a child, I remember coming into the salon before a dinner my parents were hosting for the foreign diplomats to sign the Treaty of Paris of March 1856, and asking them to sign my little album. It was fashionable at the time, as it still is, to ask the famous men of the day to sign their autograph.”

Rothschild’s collection of bought and sought letters was then given to his son James, who had moved from France to Britain after the first world war. On his death in 1957, it went to his widow, Dorothy, who left it to the Waddesdon archive in the 1980s. Surprisingly, nobody had opened the box until a French antiquarian came to Waddesdon last summer. “We then realised what was inside, and have been cataloguing since,” said Catherine Taylor, head of archives at Waddesdon.

The earliest are two letters in French from Elizabeth I. One, from 1588, is to King Henri IV of France. She addresses him as “my dear brother – the most Christian king”. “The gist of her letter is to warn Henri to watch his back with the Spanish,” said Taylor.

The second letter, written in 1583, is to the Prince de Valentinois, in which the queen thanks him for some horses. The letters both have her stylish signature. Letters by Elizabeth can fetch about £100,000 – although Waddesdon makes it very clear that none are for sale.

Nelson’s letter to a vicar, thanking him for a gift of “game” (presumably deer or bird) is from 1802, five years after he lost his right arm. The National Maritime Museum suggests that, after learning to write with his left, he was more painstaking than with his erstwhile scrawly right hand. It is signed “Nelson Bronte”, as he had been made Duke of Bronte after a Sicilian naval victory.

Byron, noted as much for his love life as his poems, has written to James Wedderburn Webster, the husband of one of his mistresses, Lady Frances Webster. There are two letters from one of the world’s most famous paramours, Madame de Pompadour, Louis XV’s lover.

Another missive has George Villiers, Duke of Buckingham – long believed to be James I’s lover – writing to Cardinal Richelieu, the French prelate, about marriage negotiations between Princess Henrietta Maria and James’s son Charles, his successor as king.

There is also a letter from the great Italian violinist Niccolò Paganini saying that he would be “happy to play for Baroness Betty” – a reference to Edmond’s mother.

Perhaps the most significant item is from the US polymath Benjamin Franklin to the Dutch scientist Jan Ingenhousz. Franklin writes of filling a balloon “with inflammable air”, and “contriving to fire it by electricity” and “match … the thunder of nature”. Dating the letter 2 September 1783, Franklin, who was US ambassador to France, writes that “tomorrow is to be signed our definitive treaty [the Treaty of Paris] which establishes for the present the Peace of Europe and America … Adieu, yours most affectionately”.

“These letters are a window into an insatiable curiosity,” says Dame Hannah Rothschild, chair of the Rothschild Foundation. “Names leap off the pages with tales of the past and stories that have been waiting to be told.”

A selection of letters will appear in an exhibition at Waddesdon, planned for spring 2025.