Question: When did Chopin return to the city where the Communist government was first overthrown?

full_context: Document 1: Dissolution of the Soviet Union: On December 7, 1989, the Communist Party of Lithuania under the leadership of Algirdas Brazauskas, split from the Communist Party of the Soviet Union and abandoned its claim to have a constitutional ``leading role ''in politics. A smaller loyalist faction of the Communist Party, headed by hardliner Mykolas Burokevičius, was established and remained affiliated with the CPSU. However, Lithuania's governing Communist Party was formally independent from Moscow's control -- a first for Soviet Republics and a political earthquake that prompted Gorbachev to arrange a visit to Lithuania the following month in a futile attempt to bring the local party back under control. The following year, the Communist Party lost power altogether in multiparty parliamentary elections which had caused Vytautas Landsbergis to become the first non-Communist president of Lithuania since its forced incorporation into the USSR.
Document 2: Dissolution of the Soviet Union: On July 1, 1988, the fourth and last day of a bruising 19th Party Conference, Gorbachev won the backing of the tired delegates for his last-minute proposal to create a new supreme legislative body called the Congress of People's Deputies. Frustrated by the old guard's resistance, Gorbachev embarked on a set of constitutional changes to try to separate party and state, and thereby isolate his conservative Party opponents. Detailed proposals for the new Congress of People's Deputies were published on October 2, 1988, and to enable the creation of the new legislature the Supreme Soviet, during its November 29–December 1, 1988, session, implemented amendments to the 1977 Soviet Constitution, enacted a law on electoral reform, and set the date of the election for March 26, 1989.
Document 3: Frédéric Chopin: From September 1823 to 1826 Chopin attended the Warsaw Lyceum, where he received organ lessons from the Czech musician Wilhelm Würfel during his first year. In the autumn of 1826 he began a three-year course under the Silesian composer Józef Elsner at the Warsaw Conservatory, studying music theory, figured bass and composition.[n 3] Throughout this period he continued to compose and to give recitals in concerts and salons in Warsaw. He was engaged by the inventors of a mechanical organ, the "eolomelodicon", and on this instrument in May 1825 he performed his own improvisation and part of a concerto by Moscheles. The success of this concert led to an invitation to give a similar recital on the instrument before Tsar Alexander I, who was visiting Warsaw; the Tsar presented him with a diamond ring. At a subsequent eolomelodicon concert on 10 June 1825, Chopin performed his Rondo Op. 1. This was the first of his works to be commercially published and earned him his first mention in the foreign press, when the Leipzig Allgemeine Musikalische Zeitung praised his "wealth of musical ideas".
Document 4: Revolutions of 1989: The events of the full - blown revolution began in Poland in 1989 and continued in Hungary, East Germany, Bulgaria, Czechoslovakia and Romania. One feature common to most of these developments was the extensive use of campaigns of civil resistance, demonstrating popular opposition to the continuation of one - party rule and contributing to the pressure for change. Romania was the only Eastern Bloc country whose people overthrew its Communist regime violently. Protests in Tiananmen Square (April to June 1989) failed to stimulate major political changes in China, but influential images of courageous defiance during that protest helped to precipitate events in other parts of the globe. On 4 June 1989 the trade union Solidarity won an overwhelming victory in a partially free election in Poland, leading to the peaceful fall of Communism in that country in the summer of 1989. Hungary began (June 1989) dismantling its section of the physical Iron Curtain, leading to a exodus of East Germans through Hungary, which destabilised East Germany. This led to mass demonstrations in cities such as Leipzig and subsequently to the fall of the Berlin Wall in November 1989, which served as the symbolic gateway to German reunification in 1990.
Document 5: Frédéric Chopin: Although it is not known exactly when Chopin first met Liszt after arriving in Paris, on 12 December 1831 he mentioned in a letter to his friend Woyciechowski that "I have met Rossini, Cherubini, Baillot, etc.—also Kalkbrenner. You would not believe how curious I was about Herz, Liszt, Hiller, etc." Liszt was in attendance at Chopin's Parisian debut on 26 February 1832 at the Salle Pleyel, which led him to remark: "The most vigorous applause seemed not to suffice to our enthusiasm in the presence of this talented musician, who revealed a new phase of poetic sentiment combined with such happy innovation in the form of his art."
Document 6: Frédéric Chopin: At the end of 1831, Chopin received the first major endorsement from an outstanding contemporary when Robert Schumann, reviewing the Op. 2 Variations in the Allgemeine musikalische Zeitung (his first published article on music), declared: "Hats off, gentlemen! A genius." On 26 February 1832 Chopin gave a debut Paris concert at the Salle Pleyel which drew universal admiration. The critic François-Joseph Fétis wrote in the Revue et gazette musicale: "Here is a young man who ... taking no model, has found, if not a complete renewal of piano music, ... an abundance of original ideas of a kind to be found nowhere else ..." After this concert, Chopin realized that his essentially intimate keyboard technique was not optimal for large concert spaces. Later that year he was introduced to the wealthy Rothschild banking family, whose patronage also opened doors for him to other private salons (social gatherings of the aristocracy and artistic and literary elite). By the end of 1832 Chopin had established himself among the Parisian musical elite, and had earned the respect of his peers such as Hiller, Liszt, and Berlioz. He no longer depended financially upon his father, and in the winter of 1832 he began earning a handsome income from publishing his works and teaching piano to affluent students from all over Europe. This freed him from the strains of public concert-giving, which he disliked.
Document 7: Dissolution of the Soviet Union: Spring 1989 saw the people of the Soviet Union exercising a democratic choice, albeit limited, for the first time since 1917, when they elected the new Congress of People's Deputies. Just as important was the uncensored live TV coverage of the legislature's deliberations, where people witnessed the previously feared Communist leadership being questioned and held accountable. This example fueled a limited experiment with democracy in Poland, which quickly led to the toppling of the Communist government in Warsaw that summer – which in turn sparked uprisings that overthrew communism in the other five Warsaw Pact countries before the end of 1989, the year the Berlin Wall fell. These events showed that the people of Eastern Europe and the Soviet Union did not support Gorbachev's drive to modernize Communism; rather, they preferred to abandon it altogether.
Document 8: Frédéric Chopin: Possibly the first venture into fictional treatments of Chopin's life was a fanciful operatic version of some of its events. Chopin was written by Giacomo Orefice and produced in Milan in 1901. All the music is derived from that of Chopin.
Document 9: Frédéric Chopin: Four boarders at his parents' apartments became Chopin's intimates: Tytus Woyciechowski, Jan Nepomucen Białobłocki, Jan Matuszyński and Julian Fontana; the latter two would become part of his Paris milieu. He was friendly with members of Warsaw's young artistic and intellectual world, including Fontana, Józef Bohdan Zaleski and Stefan Witwicki. He was also attracted to the singing student Konstancja Gładkowska. In letters to Woyciechowski, he indicated which of his works, and even which of their passages, were influenced by his fascination with her; his letter of 15 May 1830 revealed that the slow movement (Larghetto) of his Piano Concerto No. 1 (in E minor) was secretly dedicated to her – "It should be like dreaming in beautiful springtime – by moonlight." His final Conservatory report (July 1829) read: "Chopin F., third-year student, exceptional talent, musical genius."
Document 10: Soviet Union: With the rise of strong nationalist and separatist movements inside the union republics, Gorbachev tried to avert a dissolution of the Soviet Union in the post-Cold War era. A March 1991 referendum, boycotted by some republics, resulted in a majority of participating citizens voting in favor of preserving the union as a renewed federation. Gorbachev's power was greatly diminished after Russian President Boris Yeltsin played a high - profile role in facing down an abortive August 1991 coup d'état attempted by Communist Party hardliners. On 25 December 1991, Gorbachev resigned and the remaining twelve constituent republics emerged as independent post-Soviet states. The Russian Federation -- formerly the Russian SFSR -- assumed the Soviet Union's rights and obligations and is recognized as the successor state of the Soviet Union. In summing up the international ramifications of these events, Vladislav Zubok stated: ``The collapse of the Soviet empire was an event of epochal geopolitical, military, ideological and economic significance. ''
Document 11: Dissolution of the Soviet Union: On October 25, 1989, the Supreme Soviet voted to eliminate special seats for the Communist Party and other official organizations in national and local elections, responding to sharp popular criticism that such reserved slots were undemocratic. After vigorous debate, the 542-member Supreme Soviet passed the measure 254-85 (with 36 abstentions). The decision required a constitutional amendment, ratified by the full congress, which met December 12–25. It also passed measures that would allow direct elections for presidents of each of the 15 constituent republics. Gorbachev strongly opposed such a move during debate but was defeated.
Document 12: Frédéric Chopin: Back in Warsaw that year, Chopin heard Niccolò Paganini play the violin, and composed a set of variations, Souvenir de Paganini. It may have been this experience which encouraged him to commence writing his first Études, (1829–32), exploring the capacities of his own instrument. On 11 August, three weeks after completing his studies at the Warsaw Conservatory, he made his debut in Vienna. He gave two piano concerts and received many favourable reviews—in addition to some commenting (in Chopin's own words) that he was "too delicate for those accustomed to the piano-bashing of local artists". In one of these concerts, he premiered his Variations on Là ci darem la mano, Op. 2 (variations on an aria from Mozart's opera Don Giovanni) for piano and orchestra. He returned to Warsaw in September 1829, where he premiered his Piano Concerto No. 2 in F minor, Op. 21 on 17 March 1830.
Document 13: Cold War: By the 1970s, both sides had become interested in making accommodations in order to create a more stable and predictable international system, inaugurating a period of détente that saw Strategic Arms Limitation Talks and the US opening relations with the People's Republic of China as a strategic counterweight to the Soviet Union. Détente collapsed at the end of the decade with the beginning of the Soviet -- Afghan War in 1979. The early 1980s were another period of elevated tension, with the Soviet downing of Korean Air Lines Flight 007 (1983), and the ``Able Archer ''NATO military exercises (1983). The United States increased diplomatic, military, and economic pressures on the Soviet Union, at a time when the communist state was already suffering from economic stagnation. In the mid-1980s, the new Soviet leader Mikhail Gorbachev introduced the liberalizing reforms of perestroika (`` reorganization'', 1987) and glasnost (``openness '', c. 1985) and ended Soviet involvement in Afghanistan. Pressures for national independence grew stronger in Eastern Europe, especially Poland. Gorbachev meanwhile refused to use Soviet troops to bolster the faltering Warsaw Pact regimes as had occurred in the past. The result in 1989 was a wave of revolutions that peacefully (with the exception of the Romanian Revolution) overthrew all of the communist regimes of Central and Eastern Europe. The Communist Party of the Soviet Union itself lost control and was banned following an abortive coup attempt in August 1991. This in turn led to the formal dissolution of the USSR in December 1991 and the collapse of communist regimes in other countries such as Mongolia, Cambodia and South Yemen. The United States remained as the world's only superpower.
Document 14: Frédéric Chopin: Chopin took the new salon genre of the nocturne, invented by the Irish composer John Field, to a deeper level of sophistication. He was the first to write ballades and scherzi as individual concert pieces. He essentially established a new genre with his own set of free-standing preludes (Op. 28, published 1839). He exploited the poetic potential of the concept of the concert étude, already being developed in the 1820s and 1830s by Liszt, Clementi and Moscheles, in his two sets of studies (Op. 10 published in 1833, Op. 25 in 1837).
Document 15: Dissolution of the Soviet Union: On September 10, 1987, after a lecture from hardliner Yegor Ligachev at the Politburo for allowing these two unsanctioned demonstrations in Moscow, Boris Yeltsin wrote a letter of resignation to Gorbachev, who had been holidaying on the Black Sea. Gorbachev was stunned – no one had ever voluntarily resigned from the Politburo. At the October 27, 1987, plenary meeting of the Central Committee, Yeltsin, frustrated that Gorbachev had not addressed any of the issues outlined in his resignation letter, criticized the slow pace of reform, servility to the general secretary, and opposition from Ligachev that had led to his (Yeltsin's) resignation. No one had ever addressed the Party leader so brazenly in front of the Central Committee since Leon Trotsky in the 1920s. In his reply, Gorbachev accused Yeltsin of "political immaturity" and "absolute irresponsibility." No one backed Yeltsin.
ground_truth: September 1829
sub_queries: Where was the Communist government overthrown first? Answer: Warsaw
When did Chopin return to Warsaw ? Answer: September 1829