Camilla and Kate
Camilla and Kate visited the confectionary department in Fortnum & Mason's in London in 2012Reuters/Pool

As Prince William and Kate settle back home after a successful tour of India and Bhutan it's hard to remember that it wasn't always smooth sailing for the couple. A new book reveals that Camilla Parker Bowles had it in for Kate from the start and tried to convince Charles to keep her out of the family.

The problem? Kate Middleton's bloodlines. She was just too blue collar for Camilla, claims the new book, Game Of Crowns.

"Camilla is a bit of a snob," author Christopher Anderson tells the Daily Beast.

"She's an aristocrat; she has always been moving in Royal circles. She had always thought of herself as the heiress to Alice Keppel, her great-grandmother, who was the mistress of Edward VII. She was very proud of that connection, she boasted about that as a child and as an adult and that's what she intended to be: part of the Royal circle in the role of mistress to the future king, and then the king," explains Anderson.

"She did not look at Kate as someone who was worthy of joining the royal family. Kate is the first working-class woman to be accepted into the royal family. She is descended from coal miners and her mother was a flight attendant. So for all those reasons, Camilla never really felt that Kate Middleton as an individual and the Middleton family as a whole were going to be worthy of entering into the royal family."

Anderson, who has covered the royal family for 40 years, was in London when William and Kate broke up. He, like many, was "shocked," he said. "Everyone thought it was only a matter of time before William was going to ask Kate to marry him."

The break-up was due to Parker Bowles, sources told Anderson. She leaned on Charles to pressure William in 2007 to get rid of Kate. What Charles did do, Anderson believes, was to tell William to either cut it off or make a commitment.

William did cut it off with Kate — but only for a short time. He yearned for her, thanks in part to Kate's mum, Carole Middleton, who encouraged her daughter to be strong and sexy and attracting new men, rather than crying in her room alone.

"It was a strategy that worked. There were all these wonderful photographs of Kate standing in the bow of the ship in the all-women's boating regatta, and the pictures of her dancing in discotheques and cuddling up to other men and that sort of thing," Anderson recalls. "It made William insanely jealous right away and of course he wanted her back."