Born Maria Anna Paula Ferdinandine von Wurmbrand-Stuppach in Vienna, Austria, of Austro-Greek heritage, "Etti," as she was known, was putatively the elder daughter of Count Ferdinand von Wurmbrand-Stuppach (1879-1933) and his wife May Baltazzi (1885-1981), but more likely was the countess's natural child by Count Josef Gizycki. Her mother, who was a cousin of Mary Vetsera, a mistress of Crown Prince Rudolf of Austria, said that Count Gizycki's main interest in life was "the pleasuring of women in a physical way .... He was amoral and cynical, but he was a marvellous lover." (Gizycki was famed in the early 1900s because of his stormy marriage to American newspaper heiress Cissy Patterson.)
Etti von Wurmbrand-Stuppach was raised in Vienna and in Moravia, with travels to other sites throughout Europe. From the age of ten until she was twelve she was treated for tuberculosis at the Waltzaner Sanatorium in Davos which was the setting for Thomas Mann's novel The Magic Mountain.
At the age of 17 she fell in love with Count Vladschi Mittrovsky, but was forbidden to marry him because he had a blood disease. She journeyed to New York and met American railway heir Clendennin Ryan (1905-1957), marrying him on February 20, 1935, after he proposed on their third date, in Saint Patrick's Cathedral in New York. Mayor Fiorello La Guardia was best man.
The marriage lasted three months (they divorced in 1935 and the marriage was annulled in 1944), and she returned to Europe where she met Hungarian Count Paul Pálffy ab Erdöd (1890-1968) and became his fourth of eight eventual wives in 1938. They lived in Slovakia. Their life was taken up with tiger hunts in India: they both became good shots, killing stags, elephants, and antelopes. They attended the World Exposition of Shooting at Berlin, hosted by Hermann Goerring. Shortly afterwards, Pálffy became smitten with the siren-like writer Louise de Vilmorin (1902-1969) in Paris, divorced Etti in 1937, and married Louise.
On the rebound, in 1938, Etti married a Hungarian count, Tamas Esterházy von Galántha (1901-1964), and went to live in the castle of Devescer, in Hungary. They hunted, travelled, and had one daughter, Marie- Anna Berta Felicie Johanna Ghislaine Theodora Huberta Georgina Helene Genoveva, known as "Bunny".
In 1942 she journeyed abroad alone and her husband fell under the spell of heartbreaker Vilmorin. He eloped with Vilmorin (though did not marry her) and divorced Etti in 1944.
Etti's next two husbands were the Austrian Count Sigismund Berchtold (1900-1979), son of Count Leopold Berchtold, the Minister of Foreign Affairs who advised the Emperor to declare war on the Serbs, starting the First World War (they wed in 1944 and divorced in 1949). The fifth was William Deering Davis of Chicago, who had been briefly married to the silent film star Louise Brooks, in the 1930s; Plesch's marriage to Davis lasted from 1949 until their divorce in 1951.
In 1954, Etti married her last husband, Dr Arpad Plesch (1889-1974), a Hungarian lawyer, international financier and collector of rare botanical books and pornographic esoterica.
The Plesches lived on the Avenue Foch in Paris, and at the Villa Leonina at Beaulieu-sur-Mer in the South of France, where he had a famous botanical garden.
Etti's took up racing with the success noted above. After her husband's death in 1974, she took up partying and writing her memoirs, which were almost completed at the time of her death.
She died in Monte Carlo.