To ensure its survival, King Charles champions a modern monarchy

Britain's new king — the nation's oldest to become monarch at 73 — does not just follow one of history's most illustrious reigns.

He inherits a population battling a cost-of-living crisis, the war in Ukraine which has led to a ­catastrophic energy supply problem and these against a backdrop where many people across generations from the 14 Commonwealth realms are questioning the place of a constitutional monarchy in the modern world.

Read more: King Charles III inherits throne in uncertain time

One of Charles's first priorities, though, will be to attend to matters nearer to home, where infighting and scandal has plagued the royal family in recent years.

Prince Andrew's alleged involvement in a sex abuse scandal, where he was accused of having sex with a 17-year-old girl, has brought shame on the royal family during the queen's final years.

The Duke of York vehemently denied the accusations but ended up paying £12million to Virginia Giuffre rather than face a civil trial in New York. He was forced to step back from all royal duties and relinquish his military appointments.

Prince Harry too — when he resigned his royal role — was forced to give up his cherished military appointments.

Seemingly embittered and certainly estranged from some members of the royal family after his accusatory book, 'Spare', the Duke and Duchess of Sussex have also railed against the royals from their residence in California over their perceived treatment in numerous interviews with American media.

The fact that Prince Harry was invited to attend the coronation, while his wife Meghan remains at their California home, will be seen as an attempt by the king to offer an olive branch to his errant son.

Commonwealth faces potential existential threat

The Commonwealth as an entity faces possible existential threat. As head of the Commonwealth, the late queen was also queen of Jamaica, New Zealand, Papua New Guinea, Canada, Tuvalu, Australia and more than half a dozen other countries.

Combined, more people live in these nations than in the UK. All are now subjects of the new king and he faces a mixture of anti-monarchy and republican movements which have been gathering support. So, whether these countries accept the new king in the same manner in which they accepted his mother remains to be seen.

Even before Queen Elizabeth took the throne or in the early years of her reign, during an era of rapid decolonisation in the 1950s and 1960s, a majority of Britain's former colonies, including India, Pakistan and all Britain's African colonies, became republics.

In many of these places, the British monarchy was associated with the worst inequities of the empire.

In the last year there have been growing and continued calls for statements of apology and the payment of reparations to be made by the monarchy for its historical role in the transatlantic slave trade. 

Australia, where a new republican-minded government recently took office, is one major member of the Commonwealth that has declared its ambition to remove the king as head of state.

The king is philosophical, however, about the change of relationship between nations, especially amid conversations of the relevance of a white king in emerging Caribbean lands. He was in Barbados last year to witness a handover of power after centuries of British rule.

Jamaica too signalled to Prince William on his visit with the Princess of Wales last year how it would be next to follow Barbados, with Antigua and Barbuda announcing in days of the queen's death they too would sever ties with Britain within three years.

In July last year, King Charles told Commonwealth leaders in Rwanda that it was up to each member to decide whether to keep the monarch as head of state, adding that "arrangements such as these can change calmly and without rancour".

He is already prepared to face future changes without ill will. (Interestingly, there are also countries actively seek to join the Commonwealth. The latest four members, Rwanda, Mozambique, Gabon and Togo, have no historical ties to the British Empire. The last two are former French colonies.)

For all the issues surrounding the Commonwealth, King Charles selected two non-Commonwealth countries for his first state visits. France was his first choice this year and a reflection of the fact that his interests reach beyond the Commonwealth family.

In the final event he did not go, following advice over the country's unrest which was caused by nationwide protests over French President Emmanuel Macron's proposal to lower the age at which French workers can draw their pensions.

Read more: Leaving Paris in flames, an embattled Macron heads to Beijing

As a result, the king's first state visit then fell to his second choice, Germany. He spoke in German at the state banquet and said he and the Queen Consort had been "deeply touched" by the warm welcome and praised the "very special" German nation. Both nations would stand united with Ukraine, he said.  

Read more: King Charles Germany visit a soft power victory

Modernisation ambitions

Although he is of an age when many of his subjects themselves will have retired, King Charles has continued to show his desire to accommodate and innovate. He has long made it clear that he has planned for a "slimmed down" monarchy, relegating family members — cousins, nieces, nephews, even siblings—  to the sidelines.

The new monarchy will be a team of just seven key members, all senior working royals, the king himself, his wife the Queen Consort, the new Prince and Princess of Wales, the Princess Royal, and the Earl and Countess of Wessex, who are now the new Duke and Duchess of Edinburgh.

Reducing the number of royals who undertake official duties also means reducing who is funded by the sovereign grant — the public funds used to support them. This, along with the smaller coronation ceremony (half the length of his mother's), shows that King Charles is in touch with the current cost-of-living crisis in the UK.

Read more: Charles III coronation: A modern ceremony for a modern king

The king has long been interested in diversity. His coronation service includes musicians from ethnic minorities. The order of service for the ceremony itself had been delayed because of the king's desire to include roles for people of faiths other than Christianity.

He said in 2015 that he would keep the monarch's traditional title as "Defender of the Faith" but saw himself as the "protector of all faiths". 

If King Charles has had the late queen as a guide and inspiration before him — the monarch has spoken both publicly and privately of his wish to carry on from the queen's success to bolster his own legacy — he is fortunate to have his elder son, the Prince of Wales, by his side.

As a trusted confidante of the king, Prince William will have the opportunity to learn beside his father and has already inherited King Charles's passion for environmentalism, taking to the global stage with his Earthshot Prize project.

King Charles's challenges will also be Prince William's in due course. Both father and son have the chance to inspire each other and, together, realise the potential for a shared vision and to make the slimmed down royal family both effective and resilient.

By doing so, they will be hoping to ensure the monarchy survives for many generations to come.