[2] She was born in Florence in 1701, daughter of Alessandro, a lackey of African origin, nicknamed "il Moretto" (the Moorish one"), and of a Florentine woman, Maria Antonia Rapacciuoli.
Her father was in the service of castrato Francesco ("Cecchino") De Castris (c1650 – 1724), who stood as the newborn girl's godfather along with famous soprano Vittoria Tarquini as the godmother: Tesi was evidently named after the latter.
Metastasio, who had been absent from Italy since 1730 and therefore had no recent direct experience of her performances, was amazed, and in a letter to his colleague Giovanni Claudio Pasquini, he wrote: "Tesi plays in a way that surprised me, as well as the whole humanity in Vienna, of either of the two sexes".
[3] After further successful appearances at the Burgtheater in the latter half of 1748 and in 1749 (among others, in Niccolò Jommelli's Achille in Sciro and Didone abbandonata, both set to Metastasian libretti), and after having undergone a real tour de force of four new operas and two pasticcios in 1750, Tesi began to retire from her professional singing career.
In 1751 she was reported by Metastasio to be serving as the costume director at the Viennese theatre and in 1754 she appeared on stage - probably for the last time - as Lisinga in the premiere of Gluck's one-act opera Le cinesi, at Engelhartstetten, in the Schloss Hof, on the occasion of a visit of the imperial couple.
"[4] She taught singing there, having among her pupils Caterina Gabrielli and Elisabeth Teyber (1744–1816), and she would heartily receive personalities, such as Casanova or the Mozarts (father and 6-year-old son), who passed through Vienna and wished to pay homage to the old primadonna living at the Prince Saxe-Hildburghausen's.
"[7] Later, relying almost literally upon the opinions expressed by Johann Joachim Quantz, a direct witness of the singer's early performances,[8] he added: "Vittoria Tesi had by nature a masculine, strong, contralto voice.