quality:correction
Personal life

Being an Italian by descent, a Frenchman by birth, and a German by adoption, Prince Eugene signed himself appropriately using the trilingual form "Eugenio von Savoye" (Italian: Eugenio, German: von, French: Savoye).

Eugene never married and was reported to have said that a woman was a hindrance in a war, and that a soldier should never marry; according to some of his contemporaries, Eugene's loss at the 1712 Battle of Denain was due to the presence of an Italian lady that he took with him on the campaign; this was confirmed by Voltaire who reported meeting the lady in question. According to Nicholas Henderson, Eugene was called "Mars without Venus" for being a lifelong bachelor. Winston Churchill in his biography of the 1st Duke of Marlborough described Eugene as "a bachelor, almost a misogynist, disdainful of money, content with his bright sword and his lifelong animosity against Louis XIV".

During the last 20 years of his life Eugène had a relationship with one woman, Hungarian Countess Eleonore Batthyány-Strattmann, the widowed daughter of the former Hofkanzler Theodor von Strattman. Much of their acquaintance remains speculative since Eugene left no personal papers: only letters of war, diplomacy, and politics. Eugène and Eleonore were constant companions, meeting for dinner, receptions and card games almost every day till his death; although they lived apart most foreign diplomats assumed that Eleonore was his long time mistress. It is not known precisely when their relationship began, but his acquisition of a property in Hungary after the Battle of Zenta, near Rechnitz Castle, made them neighbours. In the years immediately following the War of the Spanish Succession she began to be mentioned regularly in diplomatic correspondence as "Eugen's Egeria" and within a few years she was referred to as his constant companion and his mistress. When asked if she and the Prince would marry, Countess Batthyány replied: "I love him too well for that, I would rather have a bad reputation than deprive him of his".

Rumours about Eugene's sexual orientation can be traced back to his teenage years. It has since been established that the source of these rumours was Elizabeth Charlotte, Duchess of Orléans, a renowned gossipmonger at Versailles, whose husband Philippe I, Duke of Orléans happened to be the brother of French King Louis XIV, Eugene's lifelong adversary. The Duchess documented what she claimed were youthful indiscretions involving Eugene, including alleged incidents with lackeys and pages. According to her, he was denied an ecclesiastical benefice due to his "depravity". Eugene's biographer, historian Helmut Oehler, acknowledged the Duchess's comments but attributed them to her personal animosity toward the Prince. In his memoirs, Eugene, aware of the malicious rumours, derisively addressed them, calling them "the invented anecdotes from the gallery of Versailles". Whether or not Eugene had homosexual relationships in his youth, the Duchess's remarks about him were made years later, and only after Eugene had severely humiliated the armies of her brother-in-law, the King of France. Following Eugene's departure from France at nineteen, and spanning until his death at seventy-two, there were no subsequent insinuations of homosexuality.

Being among the wealthiest and most celebrated figures of his era inevitably led to animosity for Eugene, as envy and malice trailed him from the battlefields to Vienna. His former subordinate Guido Starhemberg emerged as a persistent and bitter critic of Eugene's renown. Starhemberg, according to Montesquieu, gained notoriety at the court of Vienna as Eugene's primary rival. In a letter to a friend, Johann Matthias von der Schulenburg, another bitter rival who had served under Eugene in the War of the Spanish Succession, expressed disdain for the prince. Schulenburg, whose ambitions to command the Austrian army had been thwarted by Eugene, wrote that the prince "has no idea but to fight whenever the opportunity offers; he thinks that nothing equals the name of Imperialists, before whom all should bend the knee. He loves la petite débauche et la p---- above all things. German journalist Curt Martin Riess, reads it as "a testament to sodomy," while Eugene's primary biographer, German historian Max Braubach, interpreted "la p..." as referring to Paillardize (fornication), Prostitution, or Puterie, i.e. Whoring.

During his tenure as Governor-General of the Austrian Netherlands, Eugene developed a reputation for frequenting an exclusive brothel on Amsterdam 's Prinsengracht. The keeper of the establishment, known as Madame Therese, was familiar with Eugene's patronage. Notably, Eugene once brought the English consul in Amsterdam with him. A drawing by Cornelis Troost, housed at the Rijksmuseum, the national museum of the Netherlands, illustrates a scene in which Prince Eugene had "the 'available' women parade in review, just as he did his own troops," according to the museum. Troost based his drawing on an anecdote circulating at the time.

Eugene's other friends such as the papal nuncio, Domenico Silvio Passionei, who delivered the funeral oration of Prince Eugene, made up for the family of his own that he lacked. For his only surviving nephew, Emmanuel Thomas, the son of his brother Louis Thomas, Eugene arranged marriage with Princess Maria Theresia of Liechtenstein, Duchess of Troppau, but Emmanuel died of smallpox in 1729. Eugene then turned his attention to his grand-nephew Eugene Jean, Emanuel's only son, who now remained his last living male heir. Aiming at establishing a second Savoy state in central Italy, he requested for the young count the hand of the seven-year-old sovereign Duchess of Massa and Princess of Carrara, Maria Teresa Cybo-Malaspina (at the time under her mother's regency), obtaining the approval of Emperor Charles VI and the King of Sardinia, Charles Emmanuel III, whom he looked to as the head of the extended House of Savoy. Matrimonial agreements were signed in Vienna on 2 May 1732, but the marriage never took place due to Eugene Jean's premature death in Mannheim, where he was serving the emperor in the military, on 23 November 1734. Eugene's closest relative was now Louis Thomas's unmarried daughter and Eugene Jean's aunt, Princess Maria Anna Victoria of Savoy, whom Prince Eugene had never met (and had made no effort to do so), and who became nevertheless, in the absence of a will, the legal heiress of all his assets. She was preferred to Prince Eugene's cousin Victor Amadeus of Carignan (the son of his father's eldest brother), who was also still alive.