Susan Buckland: Memorabilia of a beloved princess

Princess Diana was often likened to her - the beautiful, extravagant, tragic Sisi, Empress Elisabeth of Austria, Queen of Hungary.

Europe was shocked by the news on September 10, 1898, that Sisi had been assassinated. Her sudden death plunged her subjects into mourning - none more so than her husband, Hungary's emperor Franz Joseph I. He had fallen head over heels in love with Sisi when she was just 15. The 23-year-old Franz Josef married his "angel Sisi" the next year in 1854 and remained devoted to her throughout her troubled and often misunderstood life.

The Sisi Museum recently opened in six rooms of the Imperial Apartments in Vienna. Being a fan of small museums with single themes, I went to the Hofburg Palace to make its acquaintance.

Tall, at 173cm and weighing only 47kg (her waist measured just 51cm), Sisi cut a striking figure.

And as the story of her life unfolds in the new museum, it becomes clear that she assiduously reined that figure in after the births of her four children. Disciplined diets and physical exercise became entrenched in her daily life.

To the raised eyebrows of the court, the athletic Sisi exercised vigorously in the palace with - imagine it - gym equipment. Some of it is on display in one of the rooms in her apartment.

Appearance mattered to Sisi. Like Princess Diana, she used her beauty to achieve her own ends. But from the age of 30 she refused to be photographed and carried parasols and decorative fans constantly. At the same time, she hated being gawped at. "It stirs my bile," she wrote to a friend.

Whenever possible she escaped the constraints of imperial protocol and the expectations of her exacting mother-in-law to enjoy the outdoor, carefree country life she had loved as a child growing up in her native Bavaria.

Sisi was a modern royal - her water closet was the height of fashion and she was the first in the palace to install a proper bathroom with a marvellous new material called linoleum.

Often her Greek tutor read from Homer while her maid brushed and dressed her luxurious hair.

Her lavish bedroom was in sharp contrast to the sleeping quarters of the Emperor who rose from his single, iron bed most days at 3.30am to start work.

I noticed a small bell in the room and overheard a guide explaining to a group of tourists that Franz Joseph rang it for Sisi "to announce himself".

However, the strain of court life reached boiling point when the Empress and Emperor lost their first child, Sophie, when she was two. Sisi's determined mother-in-law implied that Sisi's neglect had caused the child's death and took the two younger children under her care. Sisi rebelled and told her husband she would not return to the palace unless their children were returned to her.

Franz Joseph persuaded his mother (who had match-made the couple in the first place) to return the children to Sisi's care. Despite winning this battle and later giving birth to another daughter, Sisi became increasingly prey to profound melancholy.

She withdrew from public life, seeking refuge in poetry. And the cries for personal freedom became more pronounced.

"I have awakened in a dungeon

With chains on my hands

And my longing ever stronger

And Freedom! You, turned from me."

After the suicide of her only son Rudolf in 1889 she became even more reclusive and unapproachable.

She confided in her youngest daughter Marie Valerie that she often longed for death.

That moment came a year later on a fateful September morning in Geneva. Luigi Luccheni, an Italian anarchist, had intended to bump off Prince Henri of Orleans, pretender to the French throne. But Henri didn't turn up and Luccheni learned that a much greater prize was in town.

Sisi's immortality began with her untimely death. Criticism of her reclusive and seemingly eccentric behaviour was forgotten as the commercial possibilities unfolded.

The lovely and unhappy princess who had lost her life tragically was exploited by a rash of memorial coins, pictures and several movies.

The myth of Sisi was born.