Documents leading to Margaret Thatcher becoming PM to go on sale

Margaret Thatcher became the first female prime minister in Britain

PA Media Margaret Thatcher is seen from her shoulders up standing in front of a blue background. She is smiling and wearing a blue jacket. — Margaret Thatcher became the first female prime minister in Britain

Documents that led to Britain getting its first ever female Prime Minister are expected to fetch £100,000 at auction.

The nomination paper signed by Margaret Thatcher that led to her becoming leader of the Conservative Party was found in cardboard box in a Somerset garage.

It was among historic material belonging to Sir Edward du Cann, who became MP for Taunton in 1956 and went on to be chairman of the Conservative Party.

Guy Schwinge, from art consultants Hanover Forbes, who are holding the auction, said: “When I first looked through the papers the hairs went up on the back of my neck because they are of huge importance, they led to our first female prime minister.”

The document was signed by MPs who backed Thatcher becoming the party leader

“It wasn’t until 1928 until women had equal voting rights with the men in this country,” Mr Schwinge added.

“I think things do turn up but these are really very special. I have to say they are the most exciting political papers I have dealt with.

“Clearly, Margaret Thatcher was a divisive figure, not everyone adored her. But most commentators accept her place in history is secure as one of the most important leaders in the 20th century.”

Former party chairman Sir Edward had been encouraged to stand himself but his stepping aside led to the election of Mrs Thatcher and ultimately to Britain’s first female Prime Minister.

The found document is headed: ‘Election of a leader of the Conservative Party’ and is dated 11 February 1975.

It carries the signatures of the scrutineers and that of Margaret Thatcher. She won with 146 votes.

Thatcher wrote underneath ‘I consent to be nominated’ and she signed it ‘Margaret H [Hilda] Thatcher’ on 27 January 1975.

The documents will be sold at auction at Duke’s of Dorchester on 29 January 2026.

Auction watchers expect the archive could significantly outstrip the pre-sale auction estimate of £100,000.