Antonio Salieri studied under Florian Leopold Gassmann after the two met in Venice in 1766, when Gassmann, impressed by the young orphan's talent, brought the sixteen‑year‑old Salieri to Vienna on 15 June 1766. Gassmann personally oversaw every aspect of his musical education, providing instruction in violin playing, thoroughbass, counterpoint, part‑reading, and vocal composition, and grounding his theoretical training in Johann Joseph Fux’s Gradus ad Parnassum. He also arranged for Salieri to receive lessons in German, French, Latin, and Italian literature, and introduced him to influential artistic circles, including the salon of Pietro Metastasio and Christoph Willibald Gluck.
Gassmann became not only Salieri’s teacher but also his guardian and benefactor, housing him until Gassmann’s death in 1774 and securing his early career by introducing him to Emperor Joseph II. Upon Gassmann’s death, Salieri succeeded him as chamber composer to the Emperor, a position that marked the beginning of his distinguished professional life. Salieri later recalled Gassmann with deep reverence, noting that his teacher considered musical education to begin "with God" and served as a model of generosity and virtue that Salieri sought to honor by giving lessons to his own students, including Gassmann’s daughters, often without charge.