LONDON—Buckingham Palace’s decision to announce King Charles ’s cancer diagnosis breaks with a longstanding tradition of near total discretion about the British monarch’s health, as the relatively new king looks to present the 1,000-year-old regal franchise as more human and relatable.

King Charles is Britain’s largely ceremonial head of state and has the power to sign off on laws and appoint prime ministers. But unlike U.S. presidents who are expected to give granular breakdowns of the physical ailments, the unelected British monarchs face no such requirement and have for years been vague about their health.

On Monday, the palace said that during a recent hospital procedure for benign prostate enlargement “a separate issue of concern was noted” and that subsequent tests revealed this was cancer. Palace officials won’t comment on what cancer or what stage it is at, except to say it isn’t prostate cancer. It is unclear how long the king, 75, will take off from public appearances, but palace officials say he is able to undertake constitutional duties, including his weekly discussion with the British prime minister.

The statement triggered a British national parlor game, with royal watchers spending days carefully dissecting the statement for clues about the king’s actual condition. Meanwhile  medical experts are being rolled out in the media to opine about how serious his prognosis might be.

When Queen Elizabeth II had to cancel a visit to Northern Ireland three years ago after she was suddenly hospitalized, palace officials initially claimed that she was simply resting at Buckingham Palace. Days before her husband Prince Philip died in 2021, the press was told he was “in good spirits.” King Charles’ grandfather George VI had a lung removed due to cancer, a diagnosis which was hidden from the public and the monarch himself.

The days where the king or queen had to seem invincible to maintain their aura of strong leadership now appear gone. Instead a softer, more accessible British ruler is now in vogue.

“Practice has changed dramatically in three generations,” says Robert Hazell , an expert on the British constitution and professor at University College London. Several cancer charities came forward to praise Charles for being so open about his diagnosis.

Charles was under no constitutional obligation to disclose his cancer. British law only states that he can be replaced with a regent if doctors conclude he suffers infirmity of mind or body and can’t undertake his royal functions. This shift toward semi-transparency appeared to start during the pandemic. Charles caught Covid-19 twice. Queen Elizabeth also had the virus in 2022. The palace was open about the infection, sharing that the then-monarch had mild cold-like symptoms. The news sent shock waves through Britain but also made the monarchy, isolating in its various palaces, seem more relatable.

As heir in waiting, Charles was throughout his life relatively open about his various health conditions. Previously most of his health woes seem to stem from a love of horse riding and polo, which he only quit in 2005.

In 2001 he was knocked unconscious and taken to the hospital during a polo match he was playing with his sons Prince William and Prince Harry . This was preceded by a series of other tumbles including breaking his arm in the 1990s during a polo match. Horse riding also cost him a broken rib, a cracked shoulder and stitches on his cheek—all of which was relayed by his officials. Reporters were also informed of a noncancerous growth removed from his nose in 2003 and a hernia operation in 2008. The king also has a bad back, of which he has spoken, and travels on royal tours with a cushion.

Once king , the stakes are raised by the fact he is head of state to 14 nations. There is a system to ensure that the queen or some of Charles’s immediate heirs can step in to deal with legislation if the king is abroad or temporarily too unwell to act. Two of these so-called Counsellors of State can act on behalf of the sovereign. In 1974, for example, the Queen Mother and Princess Margaret declared a state of emergency and dissolved Parliament when the late Queen Elizabeth was away.

It is only if Charles were to become fully incapacitated that a more draconian step is taken and a regency is implemented, allowing his heir William to act in his name. A so-called soft regency could also be enacted where Charles more informally delegates some constitutional duties—such as the opening of parliament— to his heirs .

In reality it would have been hard for the king to pretend all was fine while not undertaking state visits abroad and engagements at home. “In more media-savvy times, the Palace could hardly have concealed the fact that a 75-year-old man went into hospital to deal with a benign prostate problem and came out with something somewhere other than in the prostate that was not benign,” says Bob Morris , an author and constitutional expert.

Write to Max Colchester at