The history of British royal coronations in London date back around a thousand years. Over that period, numerous rituals were developed, with many to feature during the coronation of Charles IIIand his wife, Camilla, on May 6.

Some rituals are almost as old as the ceremony itself, such as the royal headgear. Other aspects, like picking a signature dish — in this case, the "coronation quiche" — are modern additions.

Here are seven essential things to know about King Charles III's upcoming coronation ceremony.

1. Why is it taking place on May 6?

The royal family and the British government together picked a date that was deemed appropriate for the ceremony, yet no official reason for the May 6 date was given.

Nonetheless, the British press has pointed out how the date marks several royal family milestones. May 6 is the birthday of Charles' grandchild Archie Harrison Mountbatten-Windsor, the eldest son of Prince Harry and Meghan Markle, who was born in 2019. It is also the anniversary of the 1910 death of his great-great-grandfather, King Edward VII.

Was it the best idea to have the ceremony on his grandson's birthday? Maybe not. Daughter-in-law Markle, who is staying in Los Angeles with the kids during the coronation, is reportedly planning an extra special birthday party for her son as he turns four.

William the Conqueror was crowned on Christmas Day in 1066. Back then December 25 was considered good timing as kings were seen as God's representatives on earth.

Charles III reportedly wanted a religious date but that has not happened. His mother Elizabeth II also had her coronation in the summer, having been crowned on June 2, 1953.

2. Why Westminster Abbey?

There presumably wasn't any debate about the choice of location: British queens and kings have been crowned at Westminster Abbey since 1066, when William the Conqueror vanquished England with his army. Since then, 38 coronation ceremonies have taken place in the cathedral.

Westminster Abbey is also the site of many other important services attended by the British royal family Deutsche Welle

3. Which crown will be used?

The royal family owns several crowns. Following coronation tradition, Charles will wear St. Edward's Crown, the oldest of the British royal crowns and the centerpiece of the so-called Crown Jewels.

It was made in 1661 and first worn by King Charles II. The previous medieval crown had been melted down, as many royal jewels were sold or destroyed when England became a republic between 1649 and1660 under the leadership of Oliver Cromwell.

After the restoration of the monarchy, a new crown had to be created that closely resembled its predecessor.

Queen Elizabeth also wore St. Edward's Crown Deutsche Welle

According to the Royal Collection Trust, the crown weighs around two kilograms, is made of pure gold and adorned with rubies, amethysts and sapphires. It is estimated to be worth around $40 million (€36 million).

The crown is named after St. Edward, the last Anglo-Saxon king of England, who ruled from 1042 until his death in 1066.

4. And which crown was chosen for the queen?

On May 6, Camilla, currently Queen Consort, will become Queen Camilla.

She will be wearing the crown made for the 1911 coronation ceremony of Queen Mary, consort of King George V. According to The Guardian, this will be the first time since the 18th century that a queen consort's crown is "re-used" for a coronation.

King Charles and Camilla, the Queen Consort, attending a state banquet with German President Frank-Walter Steinmeier and his wife Elke Buedenbender Deutsche Welle

Ahead of the ceremony, an important gem will be removed from the crown: the Koh-i-noor diamond, which has recently caused controversy as it came into the possession of the British royal family under dubious circumstances. Four countries are trying to reclaim the diamond from Great Britain: India, Pakistan, Afghanistan and Iran.

Instead of the Koh-i-noor, Camilla's crown will feature some of Queen Elizabeth II's favorite stones — a tribute to the late monarch, according to the official statement.

5. What about the souvenirs?

No royal celebration takes place without the appropriate merchandising. To commemorate the coronation of King Charles III, an entire series of collectible gifts are available for fans of the royal family, whether tea towels, special coins or fridge magnets. The face of the new king even adorns British biscuit tins.

The commemorative coin that will mark the coronation of King Charles III Deutsche Welle

The British press has noted that there appear to be fewer souvenirs marking the coronation than, for example, the wedding of Prince Harry and Meghan Markle.

Beyond the official royal merch, one fan developed a special design for cereal boxes, as reported by the New York Times. The back of the boxes of the "Coronation Flakes" designed by Imran Haq, a surgeon for Britain's National Health Service, feature a cutout mask of Charles' face.

6. What's for lunch?

The "Coronation Big Lunch" is also to take place on coronation weekend. This is not a state banquet, but an initiative inviting communities, clubs, friends, families and neighbors to meet for self-organized "Big Lunches" to celebrate the coronation of their king. Traditionally, money is collected for charitable purposes.

King Charles III and Queen Camilla have also provided their recipe suggestions for the "Big Lunches." The "Coronation Quiche" was selected as a convenient dish that is inexpensive to make and can be served both cold and hot. The royal couple recommends eating a green salad and boiled new potatoes with the quiche, characterized by "delicate flavors of spinach, broad beans and fresh tarragon."

Nadiya Hussain rose to fame after winning the BBC's 'The Great British Bake Off' in 2015 Deutsche Welle

For those who feel a spinach quiche isn't spectacular enough, there are three other suggestions: lamb with an Asian marinade, a recipe by American-Chinese celebrity chef Ken Hom, the "Coronation Aubergine" by British baker and columnist Nadiya Hussain and a very special dessert by London star chef, Adam Handling.

7. Who is performing at the traditional coronation concert?

There will be a concert at Windsor Castle on the Sunday after the coronation. Big stars such as Lionel Richie, Katy Perry and opera singer Andrea Bocelli, who will sing a duet with Welsh bass-baritone Bryn Terfel, are expected.

English pop group Take That, singer-songwriter Freya Ridings, and hip-hop inspired classical pianist Alexis Ffrench will also be performing at the televised coronation concert.

Lionel Richie is expected to perform at the concert Deutsche Welle

The service will include a new composition by musical legend Andrew Lloyd Webber, best known for works such as "Jesus Christ Superstar," "Evita" or "Cats." The composer had already performed for the royal family, for Queen Elizabeth II's Platinum Jubilee.

In addition to the big superstars, there will also be a so-called "Coronation Choir" on stage, combining local choirs from all over the country. They will also be joined by a virtual choir, bringing together singers from across the Commonwealth.

Oh, and is Harry coming?

After falling out with Buckingham Palace, King Charles' youngest son, Prince Harry, is expecting a rather cool reception. Having officially left the royal family, he has still agreed to attend the event. He will, however, not be sitting in the front row like the rest of the royal family during the ceremony and will have to sit further back.

Prince Harry will drop by, but without his wife and children Deutsche Welle

Harry has not confirmed whether he will attend the concert the following day. It is believed that he will be returning to California to his family as soon as possible to celebrate son Archie's birthday with his wife and daughter.