Ludwig van Beethoven was a German composer and pianist. A crucial figure in the transition between the Classical and Romantic eras in Western art music, he remains one of the most famous and influential of all composers. His best-known compositions include nine symphonies, five piano concertos, one violin concerto, 32 piano sonatas, 16 string quartets, his great Mass the Missa solemnis, and one opera, Fidelio. Together with Mozart and Haydn, he was part of the First Viennese School. Born in Bonn, then the capital of the Electorate of Cologne and part of the Holy Roman Empire, Beethoven displayed his musical talents at an early age and was taught by his father Johann van Beethoven and by composer and conductor Christian Gottlob Neefe. At the age of 21 he moved to Vienna, where he began studying composition with Joseph Haydn, and gained a reputation as a virtuoso pianist. He lived in Vienna until his death. By his late 20s his hearing began to deteriorate, and by the last decade of his life he was almost totally deaf. In 1811 he gave up conducting and performing in public but continued to compose; many of his most admired works come from these last 15 years of his life.

Franz Peter Schubert was an Austrian composer. Schubert already died before his 32nd birthday, but was extremely prolific during his lifetime. His output consists of over six hundred secular vocal works (mainly Lieder), seven complete symphonies, sacred music, operas, incidental music and a large body of chamber and piano music. Appreciation of his music while he was alive was limited to a relatively small circle of admirers in Vienna, but interest in his work increased significantly in the decades following his death. Felix Mendelssohn, Robert Schumann, Franz Liszt, Johannes Brahms and other 19th-century composers discovered and championed his works. Today, Schubert is ranked among the greatest composers of the late Classical and early Romantic eras and is one of the most frequently performed composers of the early nineteenth century.
It was in the genre of the Lied that Schubert made his most indelible mark. Prior to Schubert's influence, Lieder tended toward a strophic, syllabic treatment of text, evoking the folksong qualities engendered by the stirrings of Romantic nationalism. Schubert expanded the potentialities of the genre like no other composer before.

(Franz) Joseph Haydn was a prolific Austrian composer of the Classical period. He was instrumental in the development of chamber music such as the piano trio and his contributions to musical form have earned him the epithets "Father of the Symphony" and "Father of the String Quartet".
Haydn spent much of his career as a court musician for the wealthy Esterházy family at their remote estate. Until the later part of his life, this isolated him from other composers and trends in music so that he was, as he put it, "forced to become original". Yet his music circulated widely and for much of his career he was the most celebrated composer in Europe.
He was a friend and mentor of Mozart, a teacher of Beethoven, with whom he formed the First Viennese School. He was also the older brother of composer Michael Haydn.