King Charles III is officially Britain’s reigning monarch.

The eldest son of the late Queen Elizabeth II and Prince Philip, Duke of Edinburgh was crowned on Saturday at London’s Westminster Abbey. Beside him was his wife, Queen Camilla.

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The 74-year-old ascended to the throne upon the death of his mother, who passed away in September 2022. The 96-year-old was Britain’s longest-reigning monarch. Charles was proclaimed Britain’s monarch two days later in an ascension ceremony broadcast for the first time on television.

"The king was nervous," British royals expert Shannon Felton Spence told Fox News Digital. "He was fiddling with the tassel in front of his robes as he walked down. I think this was unusual to see from him. But he has been thinking about this day for his entire life. He’s thought about every single detail, what means, what it should mean, deeply. He was just a kid when his mom was crowned."

"Camilla looked like a natural," Felton Spence shared. "Prince George looked so grown up and composed. And Kate Middleton looked absolutely bonkers beautiful."

The coronation ceremony dates back to the medieval period, and much of it remains unchanged. Westminster Abbey has been the setting of the ritual since William the Conqueror was crowned in 1066. A hundred heads of states attended with the U.S. maintaining its streak of a president never attending a British royal coronation. First lady Jill Biden was in attendance.

The ceremony was one of many faiths and languages to signify the new king as a unifying figure in the U.K. For the first time, a monarch was crowned in a ceremony that included the active participation of faiths other than the Church of England.

Buddhist, Hindu, Jewish, Muslim and Sikh leaders took part in various parts of the coronation. The Archbishop of Canterbury’s office described it as an act of Christian worship that reflected contemporary society. The ceremony also featured female bishops for the first time, as well as hymns and prayers sung in Welsh, Scottish, Gaelic and Irish Gaelic, as well as English.

"The king wanted the ceremony to reflect the whole of the U.K. and be representative of many backgrounds and faiths," said Felton Spence. "He wants to set the tone right from the start."

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"The service contains new elements that reflect the diversity of our contemporary society," Archbishop Justin Welby, spiritual leader of the Church of England, previously said in a statement. "It is my prayer that all who share in this service, whether they are of faith or no faith, will find ancient wisdom and new hope that brings inspiration and joy."

The coronation ceremony reflected Charles’ efforts to show that the 1,000-year-old monarchy is still relevant in a country that is much more diverse than it was when his mother was crowned 70 years ago. While the king is the supreme governor of the Church of England, the latest census showed that less than half of the population now describe themselves as Christian.

Built around the theme "Called to Serve," the coronation service began with one of the youngest members of the congregation — a Chapel Royal chorister. The moment was meant to underscore the importance of young people in the world today, according to Lambeth Palace, the home of the Archbishop of Canterbury.

The service also included many historic elements underscoring the ancient traditions through which power has been passed on to new kings and queens throughout the centuries. In the most sacred part of the service, the Archbishop of Canterbury anointed the king with oil, consecrating him and setting him apart from his subjects.

A screen covered Charles, and the anointing wasn't visible on television or to most people in the abbey, except for a few senior members of the clergy. It was then followed by a presentation of the coronation regalia, as well as sacred objects, like the orb and scepter, that symbolize the monarch’s power and responsibilities.

Prince William, the Prince of Wales and heir to the throne, pledged his loyalty to his father. This act is known as the Homage of Royal Blood.

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As the new king was crowned, the refrain "God Save the King" echoed through the abbey. After Charles was crowned, the traditional homage of the peers was replaced by an "homage of the people," in which those present at the abbey, as well as those watching on television, were invited to affirm their allegiance to the king.

Camilla was then anointed, in a form similar to that of Queen Elizabeth, the Queen Mother, in 1937. However, the 75-year-old's anointing wasn't hidden behind a screen.

Just before Charles headed off in the Gold State Coach for a procession on the streets of London, the leaders and representatives of faith communities delivered a greeting in unison. The greeting wasn't amplified out of respect for those who are observing the Jewish Sabbath and are barred from using electrical devices, Lambeth Palace confirmed.

The coronation, a more modest event in comparison to the late queen’s, featured a trimmed-down procession route to Westminster Abbey. Queen Elizabeth’s coronation was the first to be televised 70 years ago.

The Gold State Coach weighs 8,800 pounds and is pulled by eight horses. The gilded coach is so heavy that it can only be moved at a walking pace. Past monarchs have described their rides in the now 260-year-old carriage as "horrible" and "distressing" with William IV — known as the Sailor King — comparing it to "being aboard a ship tossing in a rough sea."

The expected pomp and pageantry, which dates back more than 1,000 years, was on full display with royal regalia, including five symbolic swords, two scepters and the Sovereign’s Ring, designed with a sapphire and a ruby cross set in diamonds.

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Charles was crowned king with the St. Edward’s Crown, the centerpiece of the Crown Jewels viewed by millions of people every year at the Tower of London. It features a 4.9-pound sold gold frame set with rubies, amethysts, sapphires, garnets, topazes and tourmalines, as well as a purple velvet cap and ermine band. It was worn by Elizabeth during her coronation and has been refitted for her son. At the end of the ceremony, he switched to the lighter Imperial State Crown for the procession back to Buckingham Palace.

Camilla wore Queen Mary’s Crown.

The ceremony also featured its own emoji, reflecting the first British crowning of the social media era.

While there were as many as 2,800 guests, one member of the British royal family was noticeably absent. Prince Harry attended the event without his wife Meghan Markle, who stayed behind in California with the couple’s two children, Prince Archie and Princess Lilibet. The coronation date also falls on Archie’s fourth birthday. It is believed Harry’s visit will be brief, with the Duke of Sussex heading swiftly back to the couple’s home in Montecito.

The Duke and Duchess of Sussex have publicly detailed their struggles with royal life. The king’s younger son and the former American actress stepped back as senior royals in 2020.

Harry, 38, did not take part in the service. Charles’ younger brother, Prince Andrew, also had no role in the ceremony. The Duke of York gave up royal duties after revelations of his friendship with late American financier and convicted sex offender Jeffrey Epstein. The 63-year-old was stripped of his military titles and patronages.

"Prince Harry sat next to Princess Eugenie's husband Jack Brooksbank," said Felton Spence. "He is very close with Eugenie and Jack. They are living in Frogmore Cottage now, the former U.K. home of the Duke and Duchess of Sussex."

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While Charles waited decades to become king, his long apprenticeship has been viewed favorably by several royal experts, noting it has given him more training and experience to draw upon. His mother was just 25 when she was crowned queen in 1953.

As Prince of Wales, he founded charities, including one that helps young people get jobs, education and training. He started an organic food company and dabbled in urban planning. Charles was also an early advocate for conservation and environmental protection.

The biggest controversy of Charles' life was the breakdown of his marriage to Princess Diana amid stories about his longtime relationship with Camilla Parker-Bowles, the woman who became his second wife and queen.

Charles and Diana were married from 1981 until 1996. The glamorous mother of William and Harry passed away in 1997 at age 36. Charles and Camilla married in 2005. It took years for Camilla to win many members of the public over with her charity work, sense of humor and down-to-earth style.

The ceremony was shorter in comparison to Elizabeth’s – about two hours, instead of three.

There is no official estimate of how much the coronation costs. Some reports estimated it could top 100 million pounds, or $125 million. A Buckingham Palace spokesperson said some estimates were "more fanciful than others" and that the true cost would be shared later. Charles has said he intends to reduce the number of working royals and cut expenses.