May 3, 1729:
Florian Leopold Gassmann is born in Brüx (Most), Kingdom of Bohemia of the Holy Roman Empire, the son of a goldsmith.
November 17, 1759:
Gli uccellatori, a dramma giocoso by Florian Leopold Gassmann (30) to words of Goldoni, is performed for the first time, in Teatro San Moisè, Venice.
January 27, 1760:
Filosofia ed amore, a dramma giocoso by Florian Leopold Gassmann (30) to words of Goldoni, is performed for the first time, in Teatro San Moisè, Venice.
September 1, 1760:
An overture by Johann Christian Bach (24) is performed for the first time, in Teatro Carignano, Turin to open Gli uccellatori, a dramma giocoso mostly by Florian Leopold Gassmann (31) to words of Goldoni.
April 29, 1761:
Catone in Utica, an opera seria by Florian Leopold Gassmann (31) to words of Metastasio, is performed for the first time, in Teatro San Samuele, Venice.
March 29, 1763:
Florian Leopold Gassmann (33) arrives in Vienna, having been hired by the Burgtheater to compose operas.
April 10, 1763:
Florian Leopold Gassmann (33) assumes his post at the harpsichord of the Burgtheater, Vienna for the first time.
December 26, 1763:
A second version of Ezio, a dramma per musica by Christoph Willibald Gluck (49) to words of Metastasio, is performed for the first time, in the Vienna Burgtheater. The ballet music is by Florian Leopold Gassmann (34).
October 18, 1764:
L’olimpiade, an opera seria by Florian Leopold Gassmann (35) to words of Metastasio, is performed for the first time, in the Kärntnertortheater, Vienna.
January 25, 1765:
Il trionfo d’amore, an azione teatrale by Florian Leopold Gassmann (35) to words of Metastasio, is performed for the first time, in the Schönbrunn Palace, Vienna.
August 6, 1765:
Romolo ed Ersilia, an opera by Johann Adolf Hasse (66) to words of Metastasio, is performed for the first time, in the Imperial Palace, Innsbruck, to celebrate the wedding of Archduke Leopold to the Bourbon Maria Luisa of Spain. The work does not please. This opera contains ballet music by Florian Leopold Gassmann (36), presumably the Ballo dell’opera di Romolo.
May 25, 1766:
Il viaggiatore ridicolo, a dramma giocoso by Florian Leopold Gassmann (37) to words of Goldoni, is performed for the first time, in the Kärntnertortheater, Vienna.
June 15, 1766:
Florian Leopold Gassmann (37) arrives in Vienna from Venice with a young Italian protégé who is to further his education in the city: Antonio Salieri (15).
July 1, 1766:
This is the approximate date that Florian Leopold Gassmann (37) introduces his protégé Antonio Salieri (15) to Emperor Joseph II in Vienna.
April 26, 1767:
L’amore artigiano, an opera buffa by Florian Leopold Gassmann (37) to words of Goldoni, is performed for the first time, in the Burgtheater, Vienna.
October 5, 1767:
Florian Leopold Gassmann’s (38) opera seria Amore e Psiche to words of Coltellini is performed for the first time, in the Burgtheater, Vienna as part of celebrations surrounding the betrothal of Archduchess Maria Josepha to King Ferdinando IV of Naples. Ironically, the bride in the story dies. See 15 October 1767.
January 5, 1768:
La notte critica, an opera buffa by Florian Leopold Gassmann (38) to words of Goldoni, is performed for the first time, in the Burgtheater, Vienna.
September 22, 1768:
Florian Leopold Gassmann (39) marries Barbara Damm, daughter of the Imperial hosiery knitter, in Vienna.
September 3, 1770:
La contessina, a dramma giocoso by Florian Leopold Gassmann (41) to words of Coltellini after Goldoni, is performed for the first time, in Mährisch-Neustadt, on the first day of the meeting between Emperor Joseph II and King Friedrich II.
February 23, 1771:
Empress Maria Theresia grants royal consent to Florian Leopold Gassmann (41) to form the Tonkünstler-Societät. It will provide pensions for the widows and orphans of Viennese musicians.
March 23, 1771:
An organizational meeting of the Tonkünstler-Societät takes place in the Vienna apartment of Florian Leopold Gassmann (41).
March 13, 1772:
Emperor Joseph II appoints Florian Leopold Gassmann (42) to succeed Georg von Reutter as Hofkapellmeister to the Imperial Court in Vienna, two days after Reutter’s death.
March 29, 1772:
La Betulia liberata, an oratorio by Florian Leopold Gassmann (42) to words of Metastasio, is performed for the first time, in Vienna for one of the first concerts of the Tonkünstler-Sozietät. Gassmann is musical director of the society, ex officio.
June 23, 1772:
I rovinati, a comedy by Florian Leopold Gassmann (43) to words of Giovanni Gastone Boccherini, is performed for the first time, in the Burgtheater, Vienna.
February 13, 1773:
La casa di campagna, a dramma giocoso by Florian Leopold Gassmann (43) to words possibly by Giovanni Gastone Boccherini, is performed for the first time, in the Burgtheater, Vienna.
January 20, 1774:
22:00 Florian Leopold Gassmann dies at Stadt No.206 (Strauchgasse 3), the home of Count Kraft Ernst von Oettingen-Wallerstein, in Vienna, Archduchy of Austria, aged 44 years, eight months, and 15 days. He is succeeded as Austrian court composer and conductor of the Italian opera by his young protege, Antonio Salieri (23).
January 23, 1774:
The earthly remains of Florian Leopold Gassmann are laid to rest in the Montserrater Gottesacker on the Alsergrund in Vienna.