Although Queen Elizabeth II was a monarch for seventy years – a record beaten only by Louis XIV, who became king of France aged five - we have known King Charles III for even longer. The 73-year-old who ascended the throne last week is therefore a very well-known commodity, about whom everyone will have formed their opinion long ago.

Over the years, despite all his hard work for good causes – his Prince’s Trust has helped almost one million young people since its founding in 1976 – Charles has attracted much criticism, some justified but most of it wildly unfair. As king, we will see a different person emerge from the seemingly often frustrated one who was Prince of Wales, and I believe those people who have overall negative opinions of him will change their minds.

The job of Prince of Wales is not an easy one, as Prince William will find as he tries to fill his father’s shoes. There is no constitutional prescription for what princes of Wales should do. The earlier ones in British history tended to be soldiers. Some later ones, like Edward VII and Edward VIII, simply enjoyed themselves, with the bare minimum of serious work (although Edward VII did sit on the Royal Commission on Housing for the Working Classes). By contrast, King Charles III when prince of Wales involved himself profoundly in issues that often tended to verge on the political, such a climate change (which he stated warning about as long ago as 1970), architecture, the prayer book, history-teaching, interfaith connections, and so on.

As monarch, however, many of the day-to-day tasks are specifically prescribed. Opening Parliament with a speech from the throne, investitures awarding honours, approving bills and attending some Privy Council meetings, receiving ambassadors, welcoming foreign heads of state, touring the Commonwealth and other countries, broadcasting at Christmas, opening schools and hospitals: these take up huge amounts of time throughout the year and leave little time for interfering in politics even if King Charles wanted to, and he has made it very clear in both of his speeches last week that he no longer does.

The King will meet the prime minister every Tuesday for an hour, which will give him plenty of opportunity to make his (already well-known) opinions clear to the best person to receive them, but she is under no constitutional obligation to take much more than a polite notice of them. There was a time in the early 2000s that Prince Charles wrote a series of letters to Labour cabinet ministers on every subject imaginable, from education to the plight of the Patagonian toothfish, but those days are very much over. (Most of the letters, once published in the Guardian years later, in fact showed how sensible and worthy he was in his views.)
The King’s happy and stable domestic life will be another positive aspect of the new reign. From having been unpopular back in the dark days of her extramarital affair with Prince Charles, Queen Consort Camilla is now one of the most popular members of the Royal Family, appreciated both for making her husband happy and for her own sterling qualities of charm, accessibility, unstuffiness and genuine noblesse oblige in its best sense. The tragic days of the 1990s involving Diana, Princess of Wales are now over a quarter of a century in the past, and can stay consigned there.

King Charles is ideally placed to bring the monarchy into a new era. He has been thinking about and planning for his new role for over half a century, and will have plenty of ideas of how the House of Windsor will need to evolve in order to stay relevant throughout the rest of the 21st century. If he enjoys the longevity of his parents – his mother died at 96, his father at 99 – let alone that of his maternal grandmother who lived to 101, then King Charles might spend a quarter of a century on the throne, in which time Britain will become as different a place as it was in the late 1990s, the era before iPhones, iPads and Google.

The genius of the survival of the House of Windsor - which Queen Elizabeth II knew better than anyone, and has taught her son - lies in its uncanny capacity constantly to evolve and embrace change half a step after the rest of society, but never being caught two or three steps behind. It does not try to lead fashion or push radical agendas, but neither is it a drag or a reactionary force standing against societal change once it has happened. Take the issue of divorce, for example. When Elizabeth II came to the throne, divorcees were not allowed into the Royal Enclosure at Ascot and her sister Princess Margaret was effectively banned from marrying Group Captain Peter Townsend because he was divorced. The Queen changed the rules for Ascot in 1955, and in the end three of her four children got divorced. The Windsors move with the times, and Charles III recognises that.

Charles III is king of no fewer than fifteen countries, and as an excellent forthcoming book, ‘The Enduring Crown Commonwealth’ by Michael Smith and Stephen Klimczuk-Massion, points out, he will have to fight an expected tide of republicanism in some of them after the Queen’s death. Should Australia hold another referendum, for example, it might not return the same 55% to 45% result in favour of the status quo as in November 1999. A timely visit of the new King and Queen to all the countries of the Crown Commonwealth, even the smallest ones like Tuvalu in the Pacific and Nevis in the West Indies, would be an excellent start for a fightback for constitutional monarchy, especially in those regions increasingly threatened by an aggressive China.

In his TV message on acceding, King Charles promised to continue his mother’s famous commitment made in Cape Town in 1947 to lifelong service. It will necessarily be a very different type of service than it was when he was Prince of Wales, but it will be equally effective. He said in his Buckingham Palace broadcast that his mother’s had been ‘a life well lived, a promise of destiny kept’. His will be the same.

 

Andrew Roberts, professor of history at King's College London, is best-selling biographer of Napoleon and Churchill.