WASHINGTON – Season four of the popular PBS Masterpiece series, “Downton Abbey” premiers in the U.S. on Jan. 5, but the real story of the family who lived at “Downton” is already out.

That’s because the castle’s history is not limited to the screen. The history of Highclere Castle — the breath-taking estate that serves as the setting for “Downton Abbey” — has been published by the castle’s current resident, the Countess of Carnarvon.

Following on the heels of her first book, “Lady Alma and the Real Downton Abbey,” Lady Fiona Carnarvon, otherwise known as the “real Lady of Downton Abbey,” recently published her second book, “Lady Catherine, the Earl and the Real Downton Abbey,” to further detail Highclere Castle’s rich history.

To set the scene for the story, which takes place in the 1920s, the Countess drew from the castle’s extensive archive of diaries, letters and photographs.

“I had it all in front of me, in records