Can anyone recommend the best biography of Sisi?
The one that got me started was 'The Reluctant Empress' by Brigitte Hamann.
Once you get a good background understanding of Sisi you might want to try books by her neice, Countess Marie Larisch von Moennich that include autobiographies of the authoress called 'My Life' and 'Secrets of a Royal House'. She isn't a reputable source, but they are interesting reads none-the-less, and include a lot of intrigue and Viennese court gossip regarding Prince Rudolph and Mary Vetsera who was a protege for lack of a better word of Countess Larisch.
CyrilSebastian, AD Sophie was a mentally unstable control freak who wore the pants in the family. It was her idea to have her even more unstable husband renounce the thrown in favor of their son Franz Joseph. She was the power behind the throne during his minority and refused to let that control go. A sixteen-year-old from the provinces didn't stand a chance against her, plus Sisi's own mother was Sophie's sister and she supported her sister's restrictions on her daughter. They were all inbred Hapsburgs when it comes down to it, with all the issues that brings with it.
karma chamelion, You mentioned that Archduchess Sophie had her husband Francis Charles renounce the throne. However, if Francis Charles had become Emperor of Austria, Sophie would have become Empress of Austria. How could Sophie possibly bypass the position of being Empress of Austria?
That's a very good question, I believe she thought she would have more influence with Franz Joseph than with her husband, and also that he would be a more successful monarch since he didn't outwardly suffer from the mental handicaps that his father and uncle did.