British journalist Andrew Morton became a household name in 1992 with the publication of “Diana: Her True Story,” the sensational tell-all about Princess Di and her marriage to Prince Charles. Since then, he’s become one of the leading experts on the British royal family and other celebrities.

This year, his focus is on two American women: Wallis Warfield Simpson and Meghan Markle. “Wallis in Love: The Untold Life of the Duchess of Windsor, the Woman Who Changed the Monarchy,” which came out in February, tells the story of the twice-divorced Simpson, who was at the center of a worldwide scandal when King Edward VIII abdicated the throne in 1936 to be with “the woman I love.” Eight decades after that controversy, Markle is set to marry Prince Harry next month — with the full blessing of the royal family. “Meghan: A Hollywood Princess,” his unauthorized biography of her, was released Tuesday.

You’ll see a lot of Morton leading up to the wedding on May 19 — we caught up with him during a whirlwind book tour in New York to talk about the two women.

Aside from the fact that Wallis and Meghan were both born in America and both divorced, are there any other similarities?

I think that the other similarity is their ability to network. Wallis started her cocktail parties in London, inviting diplomats, journalists, business people — mainly American — and got to know more people, she got to hear the gossip, and she got to step up the social ladder a few rungs. And I find the modern version of a cocktail party is a blog. Megan started her blog [the Tig], started her Instagram and did so in order to give her views on serious matters such as gender equality — but also to create a following and meet famous people. So she was a networker the same way Wallis was a networker, but using different tools to achieve those aims.

According to your books, both of these women are extremely ambitious.

Wallis was not ambitious in her work because she never worked, but she was socially ambitious. Meghan was ambitious in the creative field, to get parts in films and TV series, and she was socially ambitious as well — although there’s no longer any need for her to be socially ambitious.

You write that Wallis wanted to be queen and, after the abdication, desperately wanted to be called “Her Royal Highness” — which never happened. Meghan is more interested in becoming “Diana 2.0.”

I don’t know if Meghan will appreciate “Her Royal Highness” — which she is going to be called — as much as Wallis would have done. Because in those days, hierarchy, place and position was much more significant than it is today. Wallis was very focused on title and position. I don’t think Megan has given it as much thought and consideration simply because it’s not part of her intellectual lexicon.

Meghan’s never going to be queen — Harry will soon be sixth in line for the throne — but she’s marrying one of the most eligible bachelors in the world and becoming a princess. The whole thing has a certain fairy-tale aspect.

One of my favorite films is “Sliding Doors” and I’m a great believer that this whole affair is “Sliding Doors.” If she hadn’t been in London for those few days, if there hadn’t been a blind date — it was just, as Prince Harry says, that the stars were aligned. I really think that fate intervened in a bizarre, kind of unknowable way.

Just to clarify: Media reports said they met in May 2016 at the Invictus Games in Toronto, where Meghan’s show “Suits” was filmed.

That’s a thousand percent untrue. They met in July 2016 on a semi-blind date: She knew she was meeting Prince Harry and she was super excited. She was told who she was meeting and acted accordingly.

How well do you think Harry and Megan are suited for each other?

He’s always had girlfriends who are slightly out of the norm. I mean Chelsy Davy was from Zimbabwe, Cressida Bonas was an actress … He’s never gone for English Roses. And Meghan is, in many respects, perfect for him because — as he said himself — she makes him up his game.

You write that Meghan has always been outspoken?

One of the things about her which we’ve missed is that she was, as her mother said, hard-wired with a real sense of moral compass and hard-wired to give back. Meghan was an activist and an activist at an early age. In that sense, the kind of humanitarian work that the royal family does will suit her. She knows how to speak her mind.

In the engagement interview with Harry, it certainly seemed that she’s an equal partner.

She seems very different to typical previous royal brides who would be blushing, stuttering, and looking to their future husbands for help and guidance. Meghan was absolutely camera ready, not camera shy. She was articulate, she was eloquent, she was also very affectionate — openly affectionate. I find it interesting that just before the news of them dating was published in the newspapers, she told her agent, “I can’t do anymore paid engagements because my life is going to change.” She knew pretty early that this is a road that was going to lead to the altar.

Speaking of altar — anything juicy about Meghan’s first marriage to producer Trevor Engelson, which lasted two years, that we should know?

They were together for seven years, so clearly they were compatible. It’s been a bit of a closed book, but people pointed out that virtually on the day they married, she moved to Toronto.

Do you think she’s suited to be a royal wife?

In many respects, she’s very well-suited. She moves the younger generation of the royal family on a bit. She’s eloquent, she’s articulate, she’s got humanitarian work under her belt. She has a focused and defined worldview. I find it a fascinating adventure not just for Harry and Meghan but also for the royal family. As Edward VIII himself said, royal work can be very boring and very mundane. Meghan was leading a very gilded life — face of a Canadian retailer, ambassador for a charity, photoshoots here, chat shows there. She’s had to give all that up and for what? For royal walkabouts, which is like doing the red carpet without the red carpet and talking to total strangers about the weather.

Parting thoughts?

Be careful what you wish for. She wants to be famous. Now, like Croesus, she has it all.