20 Traditions Royal Brides Must Follow

1 | She must pass muster with the Queen 

The Royal Marriages Act of 1772 requires all senior royal descendants to seek the sovereign's approval for marriage. When Prince William and Kate Middleton's engagement was announced, palace officials said the Queen was "absolutely delighted," which meant she had approved of the prince's choice.

While not considered a future king, Harry needed the sovereign's approval to marry Meghan. Granny gave it and has seemingly welcomed the American divorcee with open arms into the family. Meghan's status as a divorcée was not a problem and since the 2002 ruling, she can be married in a church despite her previous divorce. Interestingly,  because he has dropped down in the line of succession since Prince Louis' birth, Prince Andrew no longer needs his mother's approval if he remarries which is, no doubt, welcome news to Sarah Ferguson, the Duchess of York. Fergie, a perennial problem for the royals, has lived with her ex-husband for years and still considers him her "best friend."

2 | She can't be Catholic 

The 1701 Act of Settlement prohibits royals from marrying Catholics. Royals may legally wed someone of any faith other than Roman Catholicism—or an Atheist. Meghan is now Anglican and a member of the Church of England after being baptized and confirmed in a secret ceremony at St James's Palace in London in March. The former actress attended a private Catholic girls' school as a child, but was raised Protestant.

3 |  Weddings must take place in specific churches

Westminster Abbey has been the popular choice for the grandest royal weddings for almost a century. King George V's daughter Mary married there in 1922, Queen Elizabeth's parents in wed at Westminster in  1923, and the Queen Elizabeth's own wedding took place there amidst great fanfare in 1947.

Kate and William chose the historic church for their nuptials in 2011. The much larger St. Paul's Cathedral was where Prince Charles and Princess Diana wed. St. George's Chapel in Windsor Castle has been the scene of royal weddings that were not bank holidays. Prince Charles and Camilla Parker Bowles received a blessing in the chapel following a civil ceremony at Windsor's Guildhall in 2005 and, of course, it's where Prince Harry and Meghan are tying the Windsor knot later this month.

4 |  The wedding dress must be white 

Ever since Queen Victoria opted to wear a white gown for her wedding to Prince Albert in 1840, royal brides have followed suit. And for more on the Royal wedding, check out 30 Fascinating Facts about British Royal Weddings.

5 |  Her guests must be smartly attired 

Women must wear tasteful "day dresses" in subtle colors that don't show too much skin. The little black dress that is an American staple is a non-starter in Britain. And, of course hats are a must. For more dos and don'ts for guests, check out these 18 Biggest Royal Wedding Guest Etiquette Dos and Don'ts.

6 | Bridesmaids are always children 

Royals brides are always accompanied by a group of  younger girls—usually between the ages of 10 and 12—as bridemaids. The Queen had eight bridesmaids and Diana had five, ranging in age from 5 to 17. Kate's bridal party was even younger and included William's goddaughter toddlers Grace van Cutsem and Camilla's granddaughter Eliza Lopes (Camilla's granddaughter).

It has been reported that Princess Charlotte and Prince George will have a role in Meghan and Harry's wedding, so be prepared for an overdose of royally adorable tykes stealing the spotlight as they walk down the aisle of St. George's Chapel. There is a possibility Meghan will break with tradition just as Kate did when chose her sister Pippa Middleton as her maid of honor who holds the dubious distinction as the oldest ever royal bridesmaid at the ripe old age of 27. Meghan's half-sister, publicity-hungry Samantha Grant, isn't even invited to the wedding, but the duchess-to-be may tap one of her close friends for the honor.

7 |  Her "Hen Party" should be low-key 

In the UK, a groom devotes an entire weekend to saying farewell to bachelorhood. The celebration is known as a stag weekend. William's party took place a month before his wedding and was hosted by Harry at a country estate away from the prying eyes of the paparazzi, with close friends James Meade, Thomas van Straubenzee and Guy Pelly.

Kate's "hen night" (we call it a bachelorette party) was arranged by her sister Pippa and was so hush-hush, no details ever made it into the press. Meghan opted for a spa trip to posh spa in the countryside with a few friends to celebrate back in March.

8 |  The guest list must be approved by the Queen

At a royal wedding, the guest list is carefully compiled by the couple and their staff and approved by the Queen. In William and Kate's case, 1,900 invitations went out by Her Majesty's command to members of the royal family (but not banished black sheep Sarah Ferguson), foreign leaders, and celebrities including David and Victoria Beckham, Elton John, Guy Ritchie, and Joss Stone, in addition to the couple's own friends and Kate's family.

For Harry and Meghan's wedding, the official word is that the couple decided to focus on family and friends and decided not to include politicians, including Prime Minister Theresa May. If we had to guess, we'd say it was exceedingly difficult for Harry to cross off his good friends former president Barack Obama and Michelle Obama from the guest list, but in order not to wade into the current choppy political climate, he was persuaded by someone (ahem) at the top.

9 |  Her bouquet must contain this one flower 

This is another tradition started by Queen Victoria married Prince Albert. She had sprigs of myrtle—known as the herb of love—in her bouquet. After the wedding, Victoria planted a myrtle shrub in her garden at the Osborne House on the Isle of Wight. Every British royal bride since has carried a bouquet containing a sprig from that very shrub. Kate carried a small, rounded bouquet—designed by Shane Connolly— with myrtle, lily-of-the-valley, hyacinth and Sweet William. Most all of the royal bridal bouquets are white.

10 |  She doesn't get to keep her bridal bouquet  

In an act of love to honor the armed forces, royals brides leave their bridal bouquet at the grave of the Unknown Warrior. The touching gesture was started by the Queen Mum in 1923, who left her flowers on the memorial in honor of her brother Fergus, who was killed in World War I in 1915.

11 |  She must arrive at and depart from the church in suitably regal fashion  

Most royal brides arrive at their wedding in horse-drawn carriage. Princess Diana's fairy-tale choice was the 1881 Glass Coach purchased for George V's coronation in 1911. Kate opted for a car albeit a very special one for the drive to Westminster Abbey with her father, Michael Middleton. Father and daughter waved to the crowd from the Queen's Rolls Royce Phantom. Its large windows allowed spectators a clear view of Kate on the way to the altar.

After the ceremony, the newlyweds departed the same carriage that carried Prince Charles and Princess Diana into the history book, a 1902 State Landau originally made for the coronation of Edward VII. Meghan and Harry have announced they will take a horse drawn carriage through Windsor after the ceremony to greet the well-wishers that are sure to line the procession route.

12 |  She can't choose her wedding band 

Royal brides' wedding bands must contain Welsh gold, which is three times more valuable than gold from Australia or South Africa. This custom began with the wedding of the Queen's late mother in 1923.

13 |  Guests are invited to a "wedding breakfast" 

Royal weddings usually take place in the morning (never later than noon) and are followed by a seated luncheon called a "wedding breakfast." Princess Diana held hers at Buckingham Palace for 120 guests. After William and Kate's wedding, 600 guests joined the newlyweds at the BP (as it is called by the royals) for a buffet-style wedding breakfast hosted by the Queen. Meghan and Harry are following suit but will hold their breakfast at Frogmore House (the site of their engagement photos) on the grounds of Windsor Castle.

14 |  The evening event is formal and for close friends only  

Later in the evening, the royal couple traditionally hosts a black-tie dinner dance for close friends and family. William and Kate's party was hosted by Prince Charles and attended by 300 revelers who partied into the early hours. Meghan and Harry will have a similar celebration. The Queen does not attend opting to leave the festivities to the younger royals.

15 |  The cake must be elaborate—and white  

While there is no official rule on this per se, royal wedding cakes have followed a familiar recipe. For decades, guests have been served a traditional English fruitcake. The towering creation is frosted in white and decorated with elaborate piping in the shape of flowers and often the couple's initials.

William and Kate had two cakes at their reception: the multi-tiered fruitcake and a chocolate biscuit cake that was specially requested by William. Meghan and Harry will be serving guests a lemon elderflower cake which may or may not be decorated with real flowers from the grounds at Windsor. Harry is a big fan of bananas, so it won't be a surprise if he has his own banana groom's cake.

16 |  She'll take on the title given to her by the Queen 

With a very few exceptions, women who marry royal heirs take on their husbands' titles and are awarded the HRH (Her Royal Highness) designation. The Queen always has the final say.

Sarah Ferguson, who married Prince Andrew, became the Duchess of York. Sophie Rhys-Jones, who wed Prince Edward, became Countess of Wessex (and was said to be disappointed she didn't merit the title of  "Duchess"). The Queen awarded William and Kate several different titles, but they are always referred to as the Duke and Duchess of Cambridge.

The odds-on favorite for Meghan and Harrys' new titles: the Duke and Duchess of Sussex. There has been one notable exception in recent years: Camilla Parker Bowles, who adopted the title Duchess of Cornwall when she married Prince Charles. Although she legally became the Princess of Wales, which had been Diana's title, it was unthinkable for the prince's former mistress to taken on the same designation. There has been much speculation about what Camilla's title will be when Charles becomes King. After the couple's wedding, the Palace announced that when Charles ascended to the throne, Camilla would be the Princess Consort, not Queen Camilla. But royal insiders have told me Charles is determined to have his longtime love be known as Queen Consort. As monarch, he has the power to award the title to his wife—even if the majority of British subjects are said to oppose the idea.

Image via Albert Nieboer/RoyalPress/dpa/Alamy Live News

17 |  She cannot be involved in politics 

Royals are never to express their political views. They don't even vote in their elections. When Diana got involved in the cause of eradicating landmines in the last year of her life, she was chastised by the British government as a "loose cannon" and a "political figure." Her response: "I'm a humanitarian figure."

These days William, Kate, Harry, and now Meghan are following in Diana's footsteps by embracing causes that were off-limits a few years ago, such as mental health and women's rights. It's clear the monarchy knows it has to modernize itself in order to stay relevant but will still stop short of endorsing specific candidates.

18 |  Autographs are off-limits 

Meghan's signature got a lot more valuable since her engagement. Royals are not permitted to sign autographs to protect against forgery. So those hundreds of wedding thank-you notes will be done by the press office. Not exactly a bad thing.

19 |  Brides must pay for the wedding dress 

Royals brides must have everything bought and paid for. The Queen is picking up the tab for her wedding. All Meghan has to pay for is her dress. We know she has expensive tastes based on the $75,000 Ralph & Russo gown she wore for her engagement portraits. The former actress can no longer accept free designer clothes or expensive beauty products like she did on visits to those Hollywood swag suites during awards' season, but with the Palace's considerable coffers and generous clothing allowances for official state visits this isn't going to be a problem.

20 |  She must change her name to become a princess 

The honor of having the princess title is reserved for ladies born into the Royal Family. For example, Kate Middleton may be a duchess, but her daughter is Princess Charlotte. The only way for a royal bride marrying into the family to become known as "princess" is to use as the feminine version of  her husband's name. Diana was never officially "Princess Diana," but was instead awarded that title by the media—and it stuck.

She was formally Diana, Princess of Wales. Meghan could use Prince Harry's official title as a princess and would then be known as HRH Princess Henry of Wales, not "Princess Meghan." Having spent over a decade in Hollywood before landing her big break and now that she's starring in the world's most popular soap opera, it's highly unlikely Meghan would ever relinquishing her given name. And for more on Meghan Markle, check out 10 Quotes That Prove Meghan Markle Will Be Running the Show After the Wedding.

Image via Paul Marriott/Alamy Live News

 Diane Clehane is a New York-based journalist and author of Imagining Diana and Diana: The Secrets of Her Style.

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