“The occupations of a constitutional monarch are grave, formal, important, but never exciting,” wrote the British journalist Walter Bagehot in his 19th-century work on the English constitution. If that’s true, no one appears to have told King Charles III.
The British monarch, who will formally be crowned king in a coronation ceremony this weekend, is perhaps the least non-exciting royal alive. Quite aside from his position as the head of the British royal family—a role that he automatically took over following the death of his mother, Queen Elizabeth II, in September—Charles’s life has always been under the spotlight, from his fairytale wedding to Princess Diana in 1981 to his falling out with his youngest son, Prince Harry, in 2021.
What distinguishes Charles from his mother, as well as most other members of his family, is his vast array of interests and hobbies. Many Britons could probably name something about the king that most would find eccentric or odd: His love of red squirrels, for example, or his passion for British hedgerows. There’s also his disdain for cube-shaped ice. Virtually everyone in the country, if not the world, knows how he feels about leaking pens.
“He’s quite quirky,” Sally Bedell Smith, author of Prince Charles: The Passions and Paradoxes of an Improbable Life, tells TIME. Quite unlike Queen Elizabeth, who had a reputation for keeping her personal views on everything beyond corgis and horses private, Charles has always been outspoken about his views and interests. The one that he is perhaps best known for is his passion for environmentalism, a cause that he took up as early as 1970 when, as the Prince of Wales, he issued a prescient warning about the “horrifying effects of pollution.” On related issues such as organic farming and sustainable fashion, Charles was ahead of his time. So committed is he to the cause of conservation that he purportedly still wears a pair of shoes that he bought in 1971 and drives a classic Aston Martin that runs on bioethanol made from cheese and wine. He has since issued more urgent calls for radical climate action.
But the monarch’s interests don’t end with the planet. Among Charles’ other noted pastimes is architecture and, in particular, how it has been stained in the modern era. He once described a proposed addition to London’s National Gallery as “a monstrous carbuncle” and even likened London’s contemporary landscape to the Battle of Britain in World War II. (“You have, ladies and gentlemen, to give this much to the Luftwaffe,” he once told attendees of an event marking the Royal Institute of British Architects’ 150th anniversary. “When it knocked down our buildings, it didn’t replace them with anything more offensive than rubble. We did that.”) A living embodiment of Charles’ architectural worldview can be found 130 miles southwest of London in Poundbury, a town featuring pastel-colored houses, abundant courtyards, and signless roads that was designed by Charles as an experimental planning project in the 1980s. Due to be completed in 2025, Poundbury has been hailed as a model for new, livable urbanism. To critics, however, it’s seen as more of a feudal Disneyland.
That Charles has so many passions—to say nothing of his interest in philosophy, homeopathic medicine, and Islam—is, in many ways, a direct consequence of his extended stint as heir to the throne, a period in which he had both the time and the resources to pursue his interests. His time as Prince of Wales “was not, by any stretch of the imagination, a life spent in waiting,” Bedell Smith says, noting his work with more than 400 charities, many of which were directly tied to his interests. “He was very busy; he was a man in a hurry.”
“He has a fogeyish side, there’s no doubt about it,” says Richard Fitzwilliams, a longtime royal expert. “But he’s also an extremely hard worker.” This perception can get lost amid Charles’ more peculiar idiosyncrasies, from his reported preference to travel with his own custom-made toilet seat to his apparent unwillingness to administer his own toothpaste. It’s little wonder that one of his biographers, royals expert Christopher Anderson, dubbed him “one of the most eccentric sovereigns Great Britain has ever had.”
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Since becoming sovereign, however, Charles had to scale his own personal views and interests back. In his first address to the nation following his mother’s death, he conceded that, as he takes on his new role, “it will no longer be possible for me to give so much of my time and energies to the charities and issues for which I care so deeply.” For many observers, this was an essential step in ensuring the continuity of the royal family as a unifying force in the country. “A monarch simply cannot go out and make pronouncements on issues that could very well alienate some portion of the British population, and for that matter the population in those nations that remain realms over which the British monarch is a head of state,” Bedell Smith says. “One of the most important roles of the monarch is to be the binding force in British society, and to do anything that runs counter to that threatens his position.”
Charles has found some ways of maintaining his individuality, though. While the monarch was reportedly blocked, for example, from attending the COP27 summit in Egypt last year, he did host a reception for others attending the summit to discuss the issue of climate change. And while he may still be the “defender of the faith,” as the supreme governor of the Church of England, Charles has also dubbed himself the “defender of faiths,” reflecting his desire to be more inclusive.
And while Charles’s coronation will be steeped in religious symbolism and tradition dating back centuries, there will still be elements of the celebration that are unique to him, if you know what to look for. The design of the ornately illustrated coronation invitations, for example, features a hedgerow border in an apparent nod to the monarch’s love of horticulture. The ceremony will also feature Greek Orthodox music, in a tribute to the king’s father, the late Duke of Edinburgh, who was born in Corfu into the Greek and Danish royal families (“He was always interested in Eastern Orthodox thinking and practices,” says Bedell Smith). The inclusion of religious leaders representing the Buddhist, Hindu, Jewish, Muslim, and Sikh traditions in the coronation underscores Charles’s efforts to reflect Britain’s diversity, as well as his own interests in non-Christian faiths.