In 1772 he was appointed virtuoso da camera at the Mannheim court, and Prince-elector Karl Theodor gave him a scholarship to enable him to continue his studies with Raaff.
Fischer is perhaps best remembered today for the role of Osmin in Die Entführung aus dem Serail, a part "tailor made" for him by Mozart and which he sang in the premiere production (first performance 16 July 1782,[4]) during the Vienna phase of his career.
[5] A year earlier, Antonio Salieri was inspired by his remarkable vocal range in composing his comic opera Der Rauchfangkehrer, writing for him the role of Herr von Bär.
When he got into a disagreement with the Imperial theatre manager, Count Orsini-Rosenberg [de], and decided to leave Vienna,[7] Mozart gave him a letter of introduction to help him as he pursued his career (successfully) in Paris.
[3] In 1787, when Fischer returned to Vienna for a visit, Mozart created for him the aria "Alcandro, lo confesso...Non sò, d'onde viene", K. 512, which he sang at a concert he gave in the Kärntnertortheater on 21 March.
[8] Mozart may also have written another work for Fischer, the recitative and aria "Così dunque tradisci...Aspri rimorsi atroci" (K.
[1] Shortly after, on April 1, Fischer wrote a 16-line poem of friendship in Mozart's album, whose last four lines (in English) are: Wilt thou my devotion know?
[9] In 1796 (28 February), Fischer participated in a memorial concert for Mozart organized by his widow Constanze; he sang excerpts from La clemenza di Tito.