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Fonseca, Daniel de


FONSECA, DANIEL DE (1672–c. 1740), Marrano physician and diplomat from Oporto (Porto), Portugal. His grandfather had been burned at the stake by the Inquisition; his father had escaped the same fate only by flight. Left behind in Portugal, his son was brought up as a priest. This did not prevent him from adhering to Judaism in secret. The secret reached the ears of the Inquisition and like his father he had to flee for his life, crossing the border into France. He studied medicine in Bordeaux, resided for a time in Paris, and then made his way to Constantinople, where he arrived in 1702. Once there, he openly embraced Judaism. Through his medical skill, De Fonseca soon became known in the Turkish capital, obtaining the confidence of many high officials. He showed himself an accomplished diplomat, consistently espousing the cause of France and thereby earning the dislike of the Court of Austria. He was appointed a physician to the French embassy, in which he occupied the position of confidential adviser. Subsequently, he became medical attendant to Prince Mavrocordato at Bucharest. On his return to Constantinople, he became physician to the sultan, continuing to occupy this office till 1730; and he was of great assistance to Charles xii of Sweden in his intrigues at the Sublime Porte against Russia and Poland. Finally he settled in Paris, where he mingled with the highest society of his age and earned the respect of Voltaire, who regarded him as "the only philosopher of his people."


Rosanes, Togarmah, 4 (1935), 188f.; E. Carmoly, Histoire des médecins Juifs (1844), 198f.; Roth, Marranos, 310–11; A. da Silva Carvalho, Daniel da Fonseca (Fr., 1939); Marquis d'Argens, Memoires (1735), 114–5.

[Abraham Haim]

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