“I remember years ago, in the ’60s, when I was a teenager, minding so much about all the things that were going on, the destruction of everything. The uprooting of trees and hedgerows and draining of wet places … this sort of white heat of progress and technology, to the exclusion of nature … this complete determination, somehow, to defeat nature.”

These aren’t the words of your typical environmental activist, but of King Charles III, as he reflected several years ago on his commitment to preserving the natural world. The video clip marked half a century of the new king’s climate activism, a career that began with a 1970 speech calling for changes in how we treat the environment, at a time when the idea of global warming—or even the notion that cutting down trees might be a bad idea—was a fringe belief at best.

Since then, the 73-year-old monarch has dedicated a large part of his life to doing something about the environmental issues that, as a youth, so occupied his mind. He has been an outspoken supporter of sustainability, organic farming, renewable energy, and biodiversity. He’s encouraged others to rethink urban design and corporate production. He skips meat a few days a week. His vintage Aston Martin runs on surplus wine and excess cheese whey. Clarence House, where he lived in London as the Prince of Wales, has solar panels. Balmoral, the summer home of the Royal Family in Aberdeenshire in Scotland, features hydroelectric turbines and biomass boilers. And at last year’s COP26, the king warned world leaders that “after billions of years of evolution, nature is our best teacher” when it comes to reducing emissions and capturing carbon, noting that “restoring natural capital, accelerating nature-based solutions, and leveraging the circular bioeconomy will be vital to our efforts.”

The king has become the UK’s head of state at a time when environmental issues have never been more at the forefront of public and political discourse—and when people are increasingly calling on their leaders to act to avert the climate crisis. But unlike other world figureheads touting climate issues, when it comes to actually believing in the need to tackle climate change, King Charles is the real deal, argues Piers Forster, professor of climate physics at the University of Leeds and a trustee of the United Bank of Carbon.

“Although he has given a lot of speeches—at Davos, etcetera—to world leaders, I’ve always got the impression that he really wants to see action on the ground, rather than nice words,” Forster says. In terms of what he’ll pay close attention to, Forster says farming and land-use change are the king’s passion: “He is no fan of big agriculture, with all its greenhouse gas emissions, fertilizer input, and lack of regard for soils or biodiversity.” This is also where UK government progress—on decarbonizing farming, increasing biodiversity, and improving soils—has been particularly poor, Forster notes.

But having ascended to the throne, it’s not a sure thing that the king will be able to speed up progress on green issues. Sir Jonathon Porritt, founder of sustainability nonprofit Forum For the Future and author of Hope in Hell: A Decade to Confront the Climate Emergency, argues that the king will actually have less power to effect change now that he is monarch. While he’s likely to still consider green issues as “crucially important to the well-being of the nation,” Porritt says, the king’s influence will be limited. “He definitely won’t engage in direct campaigns against the evil empire that is Big Oil and Gas. This is way beyond the role of a constitutional monarch.”

This is because in the UK, “the ability to make and pass legislation resides with the elected parliament of the day,” explains Stephen Clear, lead lecturer in constitutional and administrative law at Bangor University. The monarch does have to give royal assent to a bill before it can become law, but “this is considered a ‘rubber stamping’ formality with no real input from the monarch.” The convention is that the king or queen always approves laws passed by parliament—even if they don’t agree with them.

However, Clear notes that King Charles’ “black spider” memos—letters he sent to government ministers in 2004 and 2005 voicing his concerns on everything from genetic modification to global warming, farming, and social deprivation (and named after his distinct handwriting)—could suggest that he will push boundaries. Sent in a private capacity but later published, the memos were controversial due to the convention that the Royal Family be politically neutral.

On the other hand, Clear believes the king “knows his approach must change, and that he must maintain the status quo” by being an uncontroversial figurehead who remains neutral. Indeed, as soon as he ascended to the throne, King Charles declared that his activities would shift. “My life will of course change as I take up my new responsibilities,” he said in his first address to the nation. “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.”

But there’s one place where King Charles may exert a stronger influence on climate policies—and that’s the Commonwealth, the international association of countries that (mostly) used to be members of the British Empire, and which is led by the UK monarch. “The Commonwealth is very engaged on a lot of these big environmental issues, particularly the climate and biodiversity,” Porritt says. King Charles, he thinks, will be committed to making sure Commonwealth countries work effectively together to address big climate challenges.

Chris Bennett also believes the Commonwealth will play a large role in King Charles’ future plans. The cofounder of sustainability services company Evora Global, Bennett explains that while we’re currently able to only speculate on what issues the king may champion, he won’t be a toothless leader. “Taking a lead from the queen, I think he could make the most of his new soft powers,” says Bennett. “If one looks at the regular meetings that the queen had with the heads of state in the Commonwealth and the overall intent to cooperate, there is potential for convening support for initiatives like the Terra Carta.”

Part of the Sustainable Markets Initiative (SMI), which the king set up while he was the Prince of Wales, the Terra Carta was established in 2021 to guide businesses toward being more sustainable. It comprises close to 100 actions that businesses can take to put nature, people, and the planet first. Companies such as Santec, John Lewis, and the Eurasian Resources Group were among the first to sign up, and the initiative reportedly has the support of all 54 Commonwealth countries.

Signatories of the Terra Carta have come together in various projects and programs, Bennett notes, a key one being the Net-Zero Banking Alliance, a group colaunched by the UN and the Financial Services Taskforce, another product of the SMI. “This initiative has encouraged banks to make net-zero commitments and provided them with practical tools, like the Practitioners’ Guide to Net-Zero Banking,” Bennett explains. The 98 banks that are part of the alliance are responsible for over 40 percent of the world’s banking assets.

With this groundwork already laid, King Charles is likely to continue encouraging pro-environmental actions through the financial systems of Commonwealth countries, which could in turn mean more capital is made available for projects, companies, and technologies that protect and enhance nature, Bennett says.

But King Charles’ greatest green strength will perhaps lie in his legacy, and the impact his campaigning has already had on a new generation of British and Commonwealth citizens. “He has spent a huge amount of the past 50 years working with young people,” Porritt observes. “Many of the prince’s charities have been focused on young people, and young people care passionately about this stuff.”

The UK and the Commonwealth realms—including Australia, Canada, numerous Caribbean islands, and Asian and African nations—includes over 2.4 billion people, or over a quarter of the world’s population. This means that King Charles’ reach stretches farther than Buckingham Palace, and has for some time. As Porritt points out, his championing of environmental causes has not gone unnoticed by younger generations of his people.

“There aren’t a lot of older people in positions of influence and power who young people think care anything at all about these issues—most young people think they’ve been betrayed by the older generation,” Porritt explains. “Well, they’re not going to think that of King Charles III, because he was out there 50 years ago saying we’re all going to have to think differently about how we do things. People know this is something he has been passionately and authentically involved in.”

Porritt believes this connection with young people may be important in continuing the ecological fight, even as the king’s own powers become limited and his responsibilities broader. Perhaps this younger generation are the “trusted hands” Charles is now handing over environmental responsibility to. From a symbolic standpoint at least, having a figurehead who cares so passionately about the environment can be cause for hope.