Queen Elizabeth II died of old age, according to her death certificate.
The late British monarch died at 3:10 p.m. UK time (10:10 a.m. ET) on September 8 at Balmoral Castle in Ballater, Scotland, according to a document published by the National Records of Scotland on Thursday.
The cause of death is listed as old age. The document is signed by the Queen’s daughter, Princess Anne.
Britain’s longest-reigning monarch has died peacefully at the age of 96.
Her death sparked national mourning. King Charles III, who ascended the throne after his mother’s death, was formally proclaimed the new monarch of the United Kingdom on September 10.
Charles paid tribute to his mother’s historic seven-decade career, calling her “unparalleled in her duration, dedication and devotion”.
“Although we are sad, we give thanks for this most faithful life,” he said during the historic ceremony at St James’s Palace.
World leaders acknowledged the Queen’s global influence during her 70-year reign, and the world bid farewell to the King in a political funeral on 19 September.
Members of the Royal Family, dignitaries, the President and the Prime Minister gathered for a somber service at Westminster Abbey, while thousands of people thronged the surrounding streets and the 25-mile procession route from central London to Windsor. A coffin draped with the sovereign’s flag traveled by hearse to her final resting place.
Watch key moments from Queen Elizabeth II’s funeral
That evening, she was laid to rest alongside her husband of 73 years, the Duke of Edinburgh, in the King George VI Memorial Chapel. An annex to St George’s Chapel, it also houses the remains of the Queen’s father, her mother the Queen Mother and her sister Princess Margaret.
Buckingham Palace released a photograph last week revealing the sovereign’s final resting place, showing a hand-carved ledger stone made of black Belgian marble inlaid with brass letters reading the names of her parents and her husband.