Lady Diana Spencer did hers in a hastily bought off-the-rack suit from Harrods. Sophie Rhys-Jones looked like she was off for a performance review in a drab grey number and when it was Kate Middleton's turn, her choice of a blue wrap dress from the brand Issa sold out within 24-hours.
For every woman who marries into the house of Windsor going back decades, there comes a moment on their engagement day when they are forced to endure The Interview – a toothless grilling conducted by a hand selected reporter decked out in a sombre outfit.
For all intents and purposes, up until this moment the royal brides-to-be might not have possessed the power of speech, given how rarely their voices were heard in public.
Rather, the first time the world heard the carefully elocuted vowels of Diana or Sophie or Kate was when they and their intended duly sat down for The Interview.
But Meghan Markle? By the time she and a beaming Prince Harry sat down on November 27, 2017 for their chance to enthusiastically gush about one another while the cameras rolled, well, the world had already heard plenty from her.
Just over two months prior, Meghan had shocked the world by appearing on the cover of the October issue of Vanity Fair, the stunning portrait of the actress on the cover emblazoned with "She's Just Wild About Harry!"
The associated story inside was very loosely pegged to the 100th episode of her cable series, but really, there was only one thing which the world cared about: her romance with a real life Prince.
The thing is, up until Meghan turned up on the royal scene, tight-lipped silence had been the standard operating procedure for Windsor squeezes, women who have long assumed a position of decorous muteness whenever they happened to be around the press.
But none of this applied to the California native, Suits star and most consequential royal paramour since King Henry VIII first locked eyes on noted looker Anne Boleyn.
Rather, with her Vanity Fair appearance, she didn't so much break that mould as chicly smash it to smithereens, trouncing the unspoken omerta that royal girlfriends had thus far diligently adhered to.
However, looking back, should courtiers and royal aides have paid much, much more attention to that magazine moment in 2017? Were the warning signs there, even then, that the introduction of Meghan into the royal world was never, ever going to be smooth sailing?
First major signal that things were serious and altar-bound.
In retrospect, there is a clear through line between her decision to speak out then and where things stand now, that is, a woman who refused to remain docile and resolutely mum, instead using her voice when and how she sees fit (for better or worse).
(While Harry had reportedly given his blessing for the interview, Kensington Palace was by contrast merely "aware [the piece] would be coming out," according to a Telegraph report from the time, which hardly sounds like a ringing endorsement.)
Speaking to journalist Sam Kashner from the Toronto townhouse where the then 36-year-old was then living, Meghan made history. Never before had a royal girlfriend gone on the record to unabashedly declare they were in love; never before had a woman in her position opened the door even a crack into their budding relationship.
"We're in love," she said. "I'm sure there will be a time when we will have to come forward and present ourselves and have stories to tell, but I hope what people will understand is that this is our time. This is for us.
"It's part of what makes it so special, that it's just ours. But we're happy. Personally, I love a great love story."
A scant three weeks later Harry and Megan made their public debut as a couple at the Invictus Games in Toronto, arriving hand-in-hand for a tennis match and then in late November, the couple jubilantly announced their engagement in the Sunken Garden at Kensington Palace.
Now, here we are, not even four years on, picking our way through the rubble of the couple's tempestuous exit from royal life. In trying to understand how what should have been a modern-day fairytale went so badly off the rails, I wonder, should courtiers have heeded the tacit warning signs that Meghan was giving in her interview?
Reading the lengthy piece now, what immediately comes across is that essentially what Meghan was saying with this whole outing was that she would do things her own way; in essence, that would not be constrained or restricted by protocol or precedent. Rather, she would forge her own path.
If her actual words weren't loud enough then consider the stunning Peter Lindbergh images that accompanied the piece. The only thing she insisted upon, reportedly, was that Lindbergh did not airbrush out her freckles, that is, she insisted on being accepted for who she was and not who anyone else might want her to be.
Consider too that she posed barefoot in a Carolina Herrera ball gown, a heady juxtaposition of the formal and the down-to-earth, injecting a playfulness and insouciance into proceedings.
In her decision to break the royal girlfriend code of silence, Meghan made what can either be read as a brave or dicey move.
In 1978, Prince Charles had a new girlfriend, going so far as to take her on holiday with him to Klosters. Her name: Lady Sarah Spencer and she fit the future royal bride bill, given she was from a suitably aristocratic family.
The chance of a Spencer bride walking up the aisle started to look good. However, things went spectacularly pear shaped when, back in London after their Swiss getaway, Sarah committed the unforgivable sin of speaking to two journalists about their romance.
The response was swift and irrevocable with Charles telling her, "You've just done something extremely stupid." The couple's relationship was immediately over.
For the actress, the gamble clearly paid off, launching her onto the world stage and into the celebrity stratosphere.
What is frustrating is that despite the warning bells that her Vanity Fair revelations should have set off, the palace wasn't better prepared for Meghan's arrival and how to integrate her into the royal roster. After all, she went into the enterprise of the monarchy not so much as hiding her light under a bushel as carrying it confidently and proudly aloft.
Or, as veteran royal biographer and consultant on Netflix's The Crown, Robert Lacey put it last year: "The palace got this very wrong, as it always does with the second-born …. They just don't know what to do with the spare. And they certainly didn't know what to do with the spare's wife.
"They just sent her off to watch the Queen opening the Mersey Bridge … They made the mistake of dealing with the spare's wife thinking she was just a routine royal. She was never going to be a routine royal."
What makes this blinkered approach even more disappointing is that it was not as if Meghan's status as an unorthodox royal recruit was any sort of state secret.
For heavens, she told us all and then Peter Lindbergh took some lovely photos.
Meghan walked into the palace as not so much an open book but an open, glossy magazine feature story.
It's just such a shame that no one spent more time reading it.
Daniela Elser is a royal expert and a writer with more than 15 years experience working with a number of Australia's leading media titles.