The Crown producers were 'very careful' about taking Prince Harry's memoir as fact

She said: “There were nice details in there that I think were useful and, had we got it a year earlier, maybe it would have made more of a difference.”

However, Sulzberger wanted to be “very careful” about taking a personal memoir as fact.

She added: “It was very interesting to read and to be able to get his insider understanding of his experiences within the family at a time, but it didn’t affect us enormously in the end.”

Prince Harry’s book was released in January this year, just as The Crown was wrapping up its final season.

Sulzberger said they had already written and shot the majority of season six at that point, which was released in two parts in November and December.

It covered Princess Diana’s death, Harry and William’s relationship with their father while coming to terms with the tragedy, William’s schooling at Eton and his early relationship with Kate.

She commented: “We were done with quite a bit of it so we didn’t go back and reshoot because Harry’s book came out.”

However, the head of research noted that the book came out just in time to inform some episodes, including the aesthetics inside Club H.

Club H was Prince Harry and Prince William's basement club inside their father King Charles's Gloucestershire home, Highgrove.

Sulzberger explained: “It came out in time for some of the episodes where we show the Highgrove party and H Club, we were able to get a little bit of a sense of like ‘oh, it’s in a basement and there’s a light’ and those sorts of things.”

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Speaking about the legacy that the royal show has left, and the impact it has had on the public’s perception of the Royal Family, Sulzberger said that she believes the writers were “compassionate”.

She told The Telegraph: “We don’t make decisions lightly.

“I think it helps create a balance of understanding between the public and these public figures, who don’t often have a voice…I think there’s no bad thing in humanising public figures.”