Question: What is the main subject of biographies of the Bastien und Bastienne composer?

full_context: Document 1: Johann Baptist Schenk: Schenk was born in Wiener Neustadt. While still a boy he composed songs, dances and symphonies, and became a proficient violinist and keyboard and wind instrument player. In 1773 he went to Vienna to study with Georg Christoph Wagenseil. Beginning in 1777 he was composing religious works for Saint Stephen's Cathedral. In the 1780s he became a prolific composer of incidental music for plays and singspiele. His best-known singspiel is "Der Dorfbarbier", which premiered in 1796. His other compositions include numerous cantatas, ten symphonies, several concertos (including a well-known one for harp), and five string quartets. Mozart was a good friend of Schenk and Beethoven studied under him in 1793.
Document 2: Franz Xaver Wolfgang Mozart: Franz Xaver Wolfgang Mozart (26 July 1791 – 29 July 1844), also known as Wolfgang Amadeus Mozart, Jr., was the youngest child of six born to Wolfgang Amadeus Mozart and his wife Constanze. He was the younger of his parents' two surviving children. He was a composer, pianist, conductor, and teacher from the late classical period whose musical style was of an early Romanticism, heavily influenced by his father's mature style.
Document 3: Wolfgang Amadeus Mozart: Wolfgang Amadeus Mozart (/ ˈwʊlfɡæŋ æməˈdeɪəs ˈmoʊtsɑːrt / MOHT - sart; German: (ˈvɔlfɡaŋ amaˈdeːʊs ˈmoːtsaʁt); 27 January 1756 -- 5 December 1791), baptised as Johannes Chrysostomus Wolfgangus Theophilus Mozart, was a prolific and influential composer of the Classical era.
Document 4: Piece in F for Keyboard, K. 33B (Mozart): Mozart wrote this piece in pencil on the back of a circular by the Zürcher Musikkollegium (Zürich Music College) dated 30 September 1766, when the Mozart family came to the end of their Grand Tour. The circular invited sponsors, music lovers and other people who might be interested to concerts by "the young (9 years old) Master Mozart as well as his maiden sister" (Maria Anna – Nannerl) on October 7 and 9. It can be assumed that Mozart played or improvised this lively piece in one of those concerts, the programs to which are lost. Mozart wrote it on the back of the circular probably as a souvenir for the College's board; otherwise he would have used his sister's notebook or his third book of sketches (""), which is also lost. The autograph became known very late (in 1942), and so is missing from Alfred Einstein's 3rd edition of the Köchel catalogue.
Document 5: Il re pastore: Metastasio wrote the libretto in 1751, basing it on a work by Torquato Tasso called "Aminta". The libretto was picked up when Mozart (just 19 at the time) and his father saw a performance of it set to music composed by Felice Giardini – Mozart's version, however was two acts rather than Giardini's three, and has a few substantial changes. Each act lasts for around an hour in performance. The Salzburg court chaplain Varesco was largely responsible for this editing of Metastasio's libretto.
Document 6: Symphony No. 41 (Mozart): Wolfgang Amadeus Mozart completed his Symphony No. 41 in C major, K. 551, on 10 August 1788. The longest and last symphony that he composed, it is regarded by many critics as among the greatest symphonies in classical music.
Document 7: Bastien und Bastienne: Although he was very young, Mozart already had excellent vocal writing skills and a knack for parody and whimsy which would reach full flower in his later works. "" is possibly the easiest to perform of Mozart's juvenile works.
Document 8: Mitridate, re di Ponto: Mozart wrote "Mitridate" while touring Italy in 1770. The musicologist Daniel E. Freeman has recently demonstrated that it was composed with close reference to the opera "La Nitteti" by Josef Mysliveček. The latter was the opera being prepared for production in Bologna when Mozart met Mysliveček for the first time with his father in March 1770. Mysliveček visited the Mozarts frequently in Bologna during the summer of 1770 while Wolfgang was working on "Mitridate". Mozart gained expertise in composition from his older friend and also incorporated some of his musical motives into his own operatic setting. The opera was first performed at the Teatro Regio Ducal, Milan, on 26 December 1770 (at the Milan Carnival). It was a success, having been performed twenty-one times despite doubts because of Mozart's extreme youth – he was 14 at the time. No revival took place until the 20th century. This opera features virtuoso arias for the principal roles, but only two ensemble numbers: the act 2 ending duet between Aspasia and Sifare ("Se viver non degg’io"), and the brief quintet that ends the opera, very characteristic of standard baroque opera seria where the opera ends with a short "coro" or "tutti" number.
Document 9: Wolfgang Amadeus Mozart: Wolfgang Amadeus Mozart was born on 27January 1756 to Leopold Mozart (1719–1787) and Anna Maria, née Pertl (1720–1778), at 9 Getreidegasse in Salzburg. This was the capital of the Archbishopric of Salzburg, an ecclesiastic principality in what is now Austria, then part of the Holy Roman Empire. He was the youngest of seven children, five of whom died in infancy. His elder sister was Maria Anna Mozart (1751–1829), nicknamed "Nannerl". Mozart was baptised the day after his birth, at St. Rupert's Cathedral in Salzburg. The baptismal record gives his name in Latinized form, as "Joannes Chrysostomus Wolfgangus Theophilus Mozart". He generally called himself "Wolfgang Amadè Mozart" as an adult, but his name had many variants.
Document 10: Betulia liberata: The Mozart is the best known, if only because the composer's output receives more examination. Composed in March to July 1771 when Mozart was 15 years old, K. 118 (74c) is a 140-minute "azione sacra" on a text by Metastasio tracing the story of Judith and Holofernes from the biblical "". It was commissioned in March 1771 by Giuseppe Ximenes, Prince of Aragon, while Mozart and his father Leopold were on the way home to Salzburg from their first journey to Italy. It is the only oratorio Mozart ever wrote. Its two parts comprise sixteen arias, with solo or choral parts, scored for soloists, choir and orchestra. Not performed in Mozart's lifetime, "La Betulia liberata" is shaped stylistically to works by Leonardo Leo and Johann Adolph Hasse.
Document 11: Biographies of Mozart: Wolfgang Amadeus Mozart died after a short illness on 5 December 1791, aged 35. His reputation as a composer, already strong during his lifetime, rose rapidly in the years after his death, and he became (as he has remained to this day) one of the most celebrated of all composers.
Document 12: Symphony, K. 45b (Mozart): This work was only known to Ludwig Ritter von Köchel as an incipit in the catalogue of Breitkopf & Härtel, and thus it was placed in the Anhang as K. Anh. 214. Alfred Einstein then discovered a set of parts in the Berlin State Library with the title ""Synfonia Ex Bb...Del Sigr. cavaliere Amadeo Wolfgango Mozart Maestro di concerto di S.A. á Salisburgo"". Wolfgang became the Concertmaster to the Archbishop of Salzburg in November 1769, and was given the title "cavaliere" in July 1770, but as this is a later copy, this information cannot be used for dating purposes. Einstein believed the symphony to date from early 1768 on stylistic grounds; Neal Zaslaw and Gerhard Allroggen believe even earlier dates to also be possible, and Zaslaw dated the symphony cautiously to Salzburg in 1767. Einstein also believed that the symphonies in the catalogue of Breitkopf & Härtel were sent by Leopold Mozart to be published.
Document 13: London Sketchbook (Mozart): Most pieces are extremely short, normally lasting from 40 seconds to a minute; however, some span as long as four minutes in total (see K. 15t). According to the "Neue Mozart-Ausgabe", the intended purpose of this book was not for musical exercise, as once thought, rather for the young Mozart, who had just learned how to use pen and ink, to write down his own inspiration without needing anyone's help. Corrections by his father Leopold appear in pencil only.
Document 14: Mozart's birthplace: Mozart's birthplace (German: ' or ') was the birthplace of Wolfgang Amadeus Mozart at No. 9 Getreidegasse in Salzburg, Austria. The Mozart family resided on the third floor from 1747 to 1773. Mozart himself was born here on 27 January 1756. He was the seventh child of Leopold Mozart, who was a musician of the Salzburg Royal Chamber.
Document 15: Horn Concertos (Mozart): The Horn Concertos by Wolfgang Amadeus Mozart were written for his friend Joseph Leutgeb whom he had known since childhood. Leutgeb was a skilled player, as the works are very difficult to perform on the natural horn of the period, requiring lip trills, much hand-stopping, and rapid tonguing.
ground_truth: Wolfgang Amadeus Mozart
sub_queries: Bastien und Bastienne >> composer Answer: Mozart
Biographies of Mozart >> main subject Answer: Wolfgang Amadeus Mozart