An American divorcee with an acting career and a vocal advocate of womenâ€™s rights, she has been hailed as a â€œbreath of fresh air,â€ for the monarchy.
Despite husband Harry being sixth in line to the throne, who will inevitably move further down once his nephew Prince George has his own family in future, the Duke and Duchess of Sussex are two of the most popular members of the Royal Family.
But royal author Anna Pasternak thinks that Meghan should be cautious about retaining the spotlight.
Speaking to Yahoo UKâ€˜s â€˜The Royal Box,â€™ she says: â€œI think what Meghan has got to realise is that she cannot live life in the Royal Family like a A-list Hollywood star and that within the monarchy, it demands a very different set of behaviour.â€
Pasternakâ€™sÂ latest bookÂ Untitled: The Real Wallis Simpson, Duchess of Windsor explains why Simpson was maligned in history.Â Edward VIIIâ€™s relationship with the American divorcee led him to abdicate from the throne in 1936.Â
Much to the disapproval of the courtiers, theÂ couple married in 1937 and spent the rest of their lives in France.Â
Pasternak thinks the attitude and power of the courtiers hasnâ€™t changed since that period.
She says: â€œI think sheâ€™s [Meghan] heading for a very tricky situation because I think actually very little has changed in the last 80 years in terms of the power of the courtiers.
â€œAnd what Iâ€™ve discovered in my research in my book on Wallis Simpson and Princess Diana is that the one goal of the monarchy, the ultimate goal is survival and for that, the spotlight has to be on the monarch or the heir apparent.â€
The author, who broke the story about Princess Dianaâ€˜s affair with James Hewitt in 1994, adds that while Meghan wants to modernise and set her own agenda, she canâ€™t have it all.
â€œYou cannot have your freedom and this privilege,â€ Pastenak says.
â€œShe cannot be this international star on a global stage. That is the monarch, the Queen, then Charles, then William and Kate, they have to be the stars, thatâ€™s what ensures continuity of the monarchy.
â€œThe House of Windsor has done incredibly well to stay together when many other European royal houses have collapsed and theyâ€™ve done it because they recognise who has to be the main event.â€
Meghan and Harry are set to move to Frogmore Cottage in Windsor ahead of their babyâ€™s birth, expected in April. Itâ€™s thought that their new home will give them more privacy with their newborn.
And despite being weeks away from the birth, it has not been revealed where the duchess will give birth or whether the couple will choose to have a photo opportunity on the famous steps of the Lindo Wing, like the Duke and Duchess have with their three children.
Kensington Palace also confirmed last week that the pair will have their own royal household, based at Buckingham Palace, splitting from their joint one with the Cambridges.