Stéphanie (21 May 1864 – 23 August 1945) was a Belgian princess by birth and became Crown Princess of Austria through her marriage to the heir-apparent of the Habsburg dynasty, Archduke Rudolf. She was famously widowed in 1889 when Rudolf and his mistress, Mary Vetsera, were found dead in an apparent murder-suicide pact at the Imperial hunting lodge at Mayerling in the Vienna Woods.

Her grandfather Leopold I of Belgium was the country's first king. Her aunt, Charlotte of Belgium, the future ill-fated Empress of Mexico, was married to Maximilian, the brother of her future father-in law, the Austrian Emperor Franz Joseph.

Stéphanie Clotilde Louise Herminie Marie Charlotte was born at the Royal Palace of Laeken in the kingdom of Belgium. Her mother, Queen Marie Henriette, was an Archduchess of Austria by birth and aunt to the Queen of Spain. Her father, Leopold II of Belgium, finally became king of the Belgians in December 1865. The royal couple were ill-suited for each other and had an unhappy marriage. The contradictory Leopold II was serious and delicate. Marie Henriette was undisciplined, outspoken, and boisterous. Leopold was openly abrasive to her, and tried to dominate her with his criticisms and frequent infidelity. While her natural charm made Marie Henriette more popular with her Belgian subjects than her husband, she eventually retired from court life to escape him, and lived the rest of her life in Spa near the Ardennes.

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