Enea Silvio Piccolomini came from the long-established noble family Piccolomini in Siena, Italy, which included two popes: Pius II (born Enea Silvio Piccolomini) and Pius III (born Francesco Todeschini Piccolomini), as well as the Generalfeldmarschall Ottavio Piccolomini.
Young nobles left Siena individually and contacted the important Italian lobby in Vienna, hoping to obtain junior positions in some German regiment. In February 1660 Enea Silvio also left Siena to look for career in Vienna. Enea Silvio's father established him in an apartment in the imperial capital, with a page, two valets and a groom for his horses, while the youngster sought audiences with the emperor Leopold I, empress, the archduke and important ministers on the credentials of his famous ancestors.
A breakthrough came when he managed to obtain a position in the regiment of the minister Count Rabatta. Enea Silvio's situation, like that of other young German and Italian officers, was precarious. When the emperor dissolved some of his regiments in October 1660, he narrowly escaped complete unemployment and was happy to be a simple comet in his patron's cavalry regiment.
Although his court patron, the empress Claudia Felicitas of Austria died in 1676, he gained sudden popularity with the court, and in January 1677 he describes himself as being feted by the emperor and all the ministers in Vienna - appearing to have as many friends at court as if he had never left it. The last letter from November 1681 shows him negotiating through the Dowager Empress Leonora for the positions of pages for his nephews; for him, they represented two more Piccolomini and Sienese in Germany.