Elisabeth of Bavaria (24 December 1837 – 10 September 1898) was Empress of Austria and Queen of Hungary by marriage to her first cousin, Emperor Franz Joseph I. Elisabeth was born into the royal Bavarian house of Wittelsbach. Nicknamed "Sisi", she enjoyed an informal upbringing before marrying Emperor Franz Joseph I at the age of sixteen.

This portrait of Elisabeth depicting her long hair (by Franz Xaver Winterhalter, 1864), is one of two so-called "intimate" portraits of the empress; although its existence was kept a secret from the general public, it was the Emperor's favorite portrait of her and kept opposite his desk in his private study. The attached is a photo of his study at the Hofburg.

Franz Xaver Winterhalter was a German painter and lithographer, known for his portraits of royalty in the mid-19th century. His name has become associated with fashionable court portraiture. Among his best-known works are "Empress Eugénie surrounded by her ladies in waiting" and the portraits he made of Empress Elisabeth of Austria and Queen Victoria.

She never cut her hair and took meticulous care of it, washing it in a mixture of cognac and eggs. Sisi's height was 172cm. After age thirty-two, Sisi did not sit for any more portraits, and would not allow any photographs of her to be taken, so that her public image of the eternal beauty would not be challenged. The few photographs that were taken without her knowledge show a woman who was “graceful, but almost too slender”.

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