Her outfit echoed the all-black ensemble worn by Diana at a Remembrance event in 1984.
It could even be said that the Duchess of Sussex had turned to the Princess for outfit inspiration.
Meghan had wrapped up in an elegant $3000 belted wool Stella McCartney coat for the event, as she joined the Countess of Wessex and Princess Anne's husband Vice Admiral Sir Timothy Lawrence on the Whitehall balcony.
When Diana attended the event in 1984, she wore a coat of a very similar belted style, with a black pussy-bow blouse, black gloves, pearl earrings and a poppy brooch.
At the time, Diana shared the balcony with Princess Anne, Alice, Duchess of Gloucester and the Queen Mother.
While Meghan's outfit drew praise from fans, her coat designer Stella McCartney was slammed on Instagram for using the event photos to "advertise" her brand.
Posting a photo of the Duchess to her Instagram account, Stella wrote: "So honoured to have HRH Duchess of Sussex in our Autumn '19 coat at Remembrance Day service."
Social media users labelled the post "insensitive", "inappropriate" and "tacky".
"Remembrance Day is to honour those that fought for us not to use for advertising purposes. Pretty shocked," said one follower.
Another said: "Using Remembrance Day to advertise your clothes is a little disrespectful! People died and you take pictures of people showing respect for advertising purposes. Just wrong."
While another wrote: "Not an appropriate time to be selling your clothes. This is extremely tacky. I expect better of you, Stella."