SUMMARY
The article is based on the correspondence between doctor Michelangelo Tilli, the secretary of Granduke Cosimo III de’Medici in Florence and doctor Francesco Redi head physician at the Medici Court and a leading scientist in Europe. Michelangelo Tilli (1655-1750) a young physician graduated from the university of Pisa, between 1683 and 1685 travelled to the Ottoman Empire with the official charge of treating Mustafa pasha “Mussaip”, grand admiral of the Turkish fleet and son in law of Sultan Mehmed IV. It was a relevant diplomatic and political move to send a promising physician to treat the Pasha during the crucial military campaign of the Turks in Central Europe against the Holy League while Christian armies were confronting the last Ottoman attack to Vienna and Hungary. From Istanbul Tilli travelled to Belgrade and back, while the Ottomans were at war with the Hapsburg Empire. The catastrophic consequences of the siege of Vienna in September 1683 resonate in his letters and reports, to date unpublished among the literature on these events. Tilli’s letters intersect political and diplomatic information with medical therapy, botanical observation and the search for antiquities, showing the plurality of functions performed by early modern medical practitioners across imperial boundaries.