Prince William demanded 1.5 million Euros (NZD$2.36m) compensation over topless photographs of his wife Catherine after revealing how they had brought back distressing memories of the "harassment" suffered by his mother Diana.
In a statement read at the opening of a criminal case brought over pictures of the Duchess of Cambridge sunbathing topless the Prince described the decision to publish the images as "particularly shocking".
The couple are also demanding a "very significant fine" from France's Closer magazine for publishing the photographs, taken during a three-day break in a chateau in Provence, southern France, in September 2012.
William expressed his anger at the incident in a statement read to a court in Nanterre, west of Paris, where six media representatives, including three photographers, went on trial for alleged invasion of privacy.
In a damning account of the impact of the photographs on his family, the Duke of Cambridge stated that the images were "all the more painful" given the harassment linked to the death of his mother.
Princess Diana was killed in August 1997 when the car she was travelling in crashed in a Paris underpass while being pursued by photographers, after she had left the Ritz Hotel with her then boyfriend Dodi Fayed.
Her death served to compound the anger and suspicion at the behaviour of certain sections of the media felt by the Royal Family, and particularly by Diana's sons William and Harry.
In the statement Prince William said the photographs "reminded us of the harassment that led to the death of my mother, Diana Princess of Wales".
In the written declaration, read in French by the couple's lawyer Jean Veil, the Duke said: "In September 2012, my wife and I thought that we could go to France for a few days in a secluded villa owned by a member of my family, and thus enjoy our privacy.
"We know France and the French and we know that they are, in principle, respectful of private life, including that of their guests.
"The clandestine way in which these photographs were taken was particularly shocking to us as it breached our privacy."
William ended his statement by thanking the French authorities for their support and work on the investigation.
On top of the damages, Mr Veil called for a "very significant fine".
The long-lens images were spread across the front and inside pages of Closer alongside an article about the pair with the headline "Oh my God!".
One of the most intimate shots showed the Duchess of Cambridge topless and having suncream rubbed into her by Prince William.
The Duke and Duchess of Cambridge were on the terrace of a private chateau in Provence owned by Viscount Linley, the Queen's nephew, when they were photographed.
The couple launched legal proceedings soon after they were published and the French authorities banned any further reproduction of the pictures before launching an investigation into how the images were obtained.
But the photos still appeared in several other European publications.
On trial are Laurence Pieau, the editor of Closer in France, Ernesto Mauri, chief executive of the Mondadori group which owns the magazine, and Cyril Moreau and Dominique Jacovides, two Paris-based agency photographers suspected of having taken the topless photographs.
A week before Closer published the shots, another image of the couple from a different angle - and not topless - were printed in La Provence.
The paper's publishing director at the time, Marc Auburtin, and photographer Valerie Suau were also on trial. However, only the three photographers appeared in court yesterday.
Suau has admitted taking the photos but said she didn't consider she had breached their intimacy at the time.
The other two photographers both denied any involvement, despite the fact that they rented out hotel room in the area and cellular data showed they were in the immediate vicinity between September 4 and 6, 2012, and had phoned the head of their agency just after the photos were taken.
Paul-Albert Iweins, representing Closer magazine, revealed that the Duke and Duchess of Cambridge had demanded €1.5 million damages from his client, and a further €50,000 from La Provence.
He lambasted the sums as way above the French norm, saying they were the fruit of "an Anglo-Saxon reasoning of punitive damages".
Mr Iweins pointed out that when Prince Albert of Monaco sued Paris Match for publishing a photo of "his illegitimate child", it was ordered to pay €50,000 in damages.
He said that the trial was "hypocritical" as "the public and private lives of the royal couple are so closely linked as to be inseparable".
Mr Iweins added: "Two billion people watched their wedding, and we even have photos of them arriving at the maternity, leaving and now Charlotte's second birthday.
"It's of public interest to know that the potential future heirs to the throne have a solid relationship and are getting on well. It's all part of the royal business."
The verdict is due on July 4.