Well, you could start with a book on Scottish history like the excellent tome by Magnus Magnusson, but you'd also find information in any good biography about Queen Victoria. She's the one who fell in love with Balmoral in 1842 and spent a great deal of time there after Albert's death. There was a nice (sappy) movie about that era called "Her Majesty, Mrs. Brown" (1997) with Judi Dench. There's a book available called, Our Highland Home: Victoria and Albert in Scotland by Jeanne Cannizzo. Explores Queen Victoria and Prince Albert's love affair with Scotland, discussing their early journeys there and their stays at Balmoral. But getting to the heart of things, you probably would love to explore the castle's website: History of Balmoral - Balmoral Castle and Estate.
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