This is one of a series of postings of important classical music dates, from the 17th century to the present. Included are the date and location of the birth and death of composers, and the premiere date and location of the first public performance of works. When the premiere date and location is unknown, the date or year of completion of the work is given. Though reasonably comprehensive, this is a subjective list, so the choice of composers and works is mine. If you find any errors, or if you can offer a premiere date and location for a work where only the completion date or year is listed, please post a comment here.
1820
December – Franz Schubert (1797-1828) completed Quartettsatz (Movement for String Quartet) in C minor, D. 703
1821
October 16 – Franz Doppler (1821-1883) was born in Lviv, Ukraine
1822
December 10 – César Franck (1822-1890) was born in Liège, Belgium
1823
January 27 – Édouard Lalo (1823-1892) was born in Lille, France
1824
March 2 – Bedřich Smetana (1824-1884) was born in Litomyšl, Czech Republic
September 4 – Anton Bruckner (1824-1896) was born in Ansfelden, Austria
1825
April – Franz Schubert (1797-1828) completed Ave Maria, op. 52, no. 6
October 25 – Johann Strauss II (1825-1899) was born in Vienna, Austria
1826
August 26 – Overture to A Midsummer Night’s Dream in E major, op. 21 by Felix Mendelssohn (1809-1847) was first performed in Berlin, Germany
October – Ludwig van Beethoven (1770-1827) completed String Quartet No. 16 in F major, op. 135
1827
March 26 – Ludwig van Beethoven (1770-1827) died in Vienna, Austria
November – Franz Schubert (1797-1828) completed Piano Trio in E♭ major, D. 929
1828
March 23 – String Quartet No. 16 in F major, op. 135 by Ludwig van Beethoven (1770-1827) was first performed in Vienna, Austria
May – Franz Schubert (1797-1828) completed Three Piano Pieces, D. 946
November 19 – Franz Schubert (1797-1828) died in Vienna, Austria
December 14 – Symphony No. 6 in C major, D. 589 by Franz Schubert (1797-1828) was first performed in Vienna, Austria
1829
Frédéric Chopin (1810-1849) completed Étude in C major, op. 10, no. 1, “Waterfall”
October 4 – Mass No. 6 in E♭ major, D. 950 by Franz Schubert (1797-1828) was first performed in Vienna, Austria