£187m of Windsor family wealth hidden in secret royal wills

Generations of the royal family have concealed details of assets worth more than £180m through a series of legal applications that have been granted in total secrecy.

The assets are outlined in 33 wills that were drawn up by members of the Windsor family over more than a century.

The family have been able to keep secret the contents of the wills by securing a special carve-out from a law that normally requires British wills to be published.

The sealing of the wills has enabled the Windsors to avoid the public seeing what kinds of assets - such as property, jewels and cash - have been accumulated by members of the royal family and how these were then distributed to, for example, relatives, friends or staff.

However, the Guardian has been able to calculate the overall size of the wealth passed down by many members of the family, as the value of their estates has been published in public registers and declassified government files.

This shows that the Windsor family, whose wealth is opaque, have been able to keep secret wills that contain assets totalling - at today's figures - £187m. Because the contents remain secret, some assets may have appeared in multiple wills and been counted more than once.

At the top of the league is the Duke of Fife, who married Princess Louise, a daughter of King Edward VII. When the duke died in 1912, he left behind a fortune that is worth the equivalent today of £79m.

Nine other wills contain assets worth between £5m and £11.7m if translated into today's figures. They include Princess Margaret, the Queen's sister, who left £7.7m (£11.5m at today's prices) when she died in 2002.

Wills drawn up by a succession of minor royals including grandchildren of Queen Victoria have been kept secret. One of the more remote relatives was a member of the Danish royal family, Prince George Valdemar Carl Axel, who was born in Denmark and was a second cousin to Prince Philip. He lived in Britain and married a viscountess who was a distant relative of the royal family.

His will was sealed in London after his death in 1986. His estate was valued at £785,000 (£1.8m at today's prices).

The arcane practice of keeping secret the wills of members of the royal family is due to come under scrutiny in a court case that starts on Wednesday. The Guardian is taking legal action to challenge a decision to exclude the media from a court hearing that resulted last year in a ruling that kept secret the Duke of Edinburgh's will.

For decades, lawyers for the royal family have obtained legal orders from high court judges to have the contents of wills kept confidential after relatives have died. Since 1911, all the court hearings in which senior judges granted these orders have been held behind closed doors.

This practice has been controversial, since wills belonging to members of the general public are ordinarily made public after they die. They are generally published in order to ensure that they are correctly implemented and are not subjected to any fraud. Legislation from the 1800s bans the publication of the monarch's will.

For more than a century, high court judges who decided that the wills should be kept secret also concluded that their judgments explaining their rulings should not be published.

The first judgment to be made public was last September, when a high court judge - Sir Andrew McFarlane, the president of the family division - published his ruling that Prince Philip's will should not be made public.

He decided that the wills of senior royals should be confidential as it was "necessary to enhance the protection afforded to the private lives of this unique group of individuals, in order to protect the dignity and standing of the public role of the sovereign and other close members of her family".

Lawyers for Philip also successfully applied to keep secret the value of the assets contained within his will.

As with all the other hearings, the media were prevented from attending or even being allowed to argue why they should be able to attend.

In its legal challenge to be heard over two days, the Guardian is arguing that the high court failed to properly consider whether the press should be allowed to attend the hearing, and that its failure to allow the media to make representations constitutes such a serious interference with the principle of open justice that the case should be reheard.

The application is being opposed by the attorney general's department, which declined to comment as the legal case was being heard.

Buckingham Palace declined to comment in detail. A spokesperson said: "The treatment of wills is a matter for the executors of estates." The spokesperson added that the executors of any Briton could apply to have a will sealed. It is not known how many wills of Britons - outside of the royal family - have been closed after legal applications.

Date of probate unknown

Husband of Elizabeth II. His family applied not only to seal his will but also to keep secret the value of his wealth.Value of estate: confidential

Probate London 15 April 2002

Wife of King George VI and mother to the current queen, Elizabeth II. The royal family chose not to publish the value of her wealth after her death.Value of estate: confidential

Probate London 24 June 2002

Youngest daughter of King George VI and Queen Elizabeth, the Queen Mother, and younger sister of Elizabeth II. Her family announced the value of her wealth.Value of estate: £7,700,176 (£11.5m)

Probate London 20 May 1987

Danish prince who was the second cousin of Prince Philip, the Duke of Edinburgh. He lived in Britain for some time and married a viscountess who was a remote relative of the royal family.Value of estate: £785, 236 (£1.8m)

Probate London 30 June 1981

Last surviving grandchild of Queen Victoria.Value of estate: £182, 185 (£567,100)

Probate London 27 February 1980

Uncle of Prince Philip and second cousin once removed of Elizabeth II. He was the last viceroy of India.Value of estate: £2,196, 494 (£7.6m)

Probate London 9 September 1974

Son of George V who was governor general of Australia in the 1940s.Value of estate: £734, 262 (£5.6m)

Probate London 17 April 1974

Granddaughter of Queen Victoria.Value of estate: £917,199 (£7m)

Administration (with will) London 17 November 1972

As Edward VIII, he abdicated the throne in 1936 to marry an American divorcee, Wallis Simpson. Afterwards they lived abroad and accrued millions. This figure represents only his wealth based in England and Wales.Value of estate: £7,845 (£75,000)

Probate London 24 October 1972

Grandson of George V and cousin of Elizabeth II who died in an air crash at the age of 30.Value of estate: £416,001 (£3.9m)

Probate London 11 October 1968

Greek princess who married Prince George, the fourth son of King George V.Value of estate: £76,166 (£940,600)

Probate London 22 December 1965

Daughter of George V. According to declassified documents, the current Queen - her niece - specifically asked for her will to be sealed.Value of estate: £347, 626 (£4.7m)

Probate London 23 April 1959

Eldest grandchild of King Edward VII

According to an official account, the high court judge who allowed this will to be sealed accepted that there was no special justification but decided "it was desirable".Value of estate: £86,217 (£1.4m)

Probate London 12 March 1957

Granddaughter of Queen Victoria.Value of estate: £107,644 (£1.8m)

Probate London 5 August 1953

Queen and wife of George V. Grandmother to Queen Elizabeth II.Value of estate: £406, 407 (£7.9m)

Probate London 20 May 1948

Granddaughter of Queen Victoria.Value of estate: £52,435 (£1.3m)

Probate Llandudno 22 March 1946

Granddaughter of Edward VII.Value of estate: £44,008 (£1.2m)

Probate Llandudno 14 May 1943. This appears to be an error in the list of wills published by the high court in November 2021, as she died in 1944.

Daughter of Queen Victoria.Value of estate: unknown

Probate Llandudno 27 January 1943

Son of George V. He was killed in a military air crash in 1942.Value of estate: £157,735 (£5m)

Probate Llandudno 10 March 1942

Son of Queen Victoria. He was appointed Canada's governor general.Value of estate: £150,677 (£4.9m)

Probate London 7 February 1940

Daughter of Queen Victoria.Value of estate: £239, 260 (£9.3m)

Probate London 1 March 1939

Grandson of Queen Victoria. He was a British military officer and the governor general of South Africa.Value of estate: £109,418 (£4.9m)

Administration (with will) London 16 February 1939

Wife of King Haakon VII of Norway, and youngest daughter of King Edward VII.Value of estate: £7,941 (£362,400)

Probate London 11 March 1936

Daughter of King Edward VII.Value of estate: £237,455 (£11.7m)

Probate 13 April 1931 and London 5 June 1934

Eldest daughter of King Edward VII. Given the title Princess Royal in 1905.Value of estate: £46, 383 (£2.2m)

Probate London 25 May 1927

Born in Hanover, the elder daughter of a German prince. In the UK she held the title of princess as a male-line great-granddaughter of King George III.Value of estate: £ 85 (£3,700)

Daughter of Queen Victoria. She married Prince Christian of Schleswig-Holstein.

Newly declassified documents show that after she died in 1923, her executors attempted to convince tax inspectors that there was no requirement to pay death duties - an opinion apparently supported by King George V. The inspectors rejected their argument. At the time of her death, she was receiving the equivalent today of £250,000 a year from the public purse tax-free. The executors did not apply for probate.Value of estate: unknown

Probate London 29 December 1922

Wife of Prince Leopold, youngest son of Queen Victoria.Value of estate £177,312 (resworn £183,053) (£7.2m)

Probate London 15 June 1922

Grandson of Queen Victoria. Originally known as Prince Leopold of Battenberg.Value of estate: £4,049 (£160,600)

Administration (with will) London 13 December 1920

Granddaughter of George III. She married into the Grand Ducal House of Mecklenburg-Strelitz before returning to Britain in later life.Value of estate: £57,282 (£1.7m)

Probate London 1 May 1917Youngest grandchild of Queen Victoria. He was killed in action in 1914.Value of estate: £3,147 (£152,400)

Probate London 24 May 1912

Wealthy Scottish landowner who married Princess Louise, a daughter of King Edward VII and Queen Alexandra.Value of estate: £1m (£79.7m)

Probate London 17 February 1911

Brother of Queen Mary of Teck, wife of George V. Mary persuaded a judge to keep his will closed to head off a scandal as it was alleged that he had left valuable family jewels to a mistress.Value of estate: £23,154 (£1.9m)