Question: What Russian composer contributed to the violin concerto?
Context: A violin concerto is a concerto for solo violin (occasionally, two or more violins) and instrumental ensemble, customarily orchestra.  Such works have been written since the Baroque period, when the solo concerto form was first developed, up through the present day.  Many major composers have contributed to the violin concerto repertoire, with the best known works including those by Bach, Bartók, Walton, Beethoven, Brahms, Bruch, Mendelssohn, Mozart, Paganini, Prokofiev, Shostakovich, Sibelius, Tchaikovsky, and Vivaldi. The Violin Concerto in G major, Op. 46, is the sole violin concerto by Anton Rubinstein.  Written in the Romantic style in 1857, when the composer was 28 years old, it was published by C.F. Peters in 1859 with a dedication to violinist Henryk Wieniawski.  At that time, establishment of the first professional conservatory in Russia was still a matter under discussion; the work makes virtuoso demands of its soloist; and its character is more German in the tradition of Mendelssohn than Russian, likely all factors in its failure to claim a place in the standard repertory. Pyotr Ilyich Tchaikovsky ( ; Russian: Пётр Ильи́ч Чайко́вский ; 25 April/7 May 1840 – 25 October/6 November 1893), often anglicized as Peter Ilich Tchaikovsky, was a Russian composer of the romantic period, some of whose works are among the most popular music in the classical repertoire.  He was the first Russian composer whose music made a lasting impression internationally, bolstered by his appearances as a guest conductor in Europe and the United States.  Tchaikovsky was honored in 1884, by Emperor Alexander III, and awarded a lifetime pension. François Boucher (1860c.  1936) was a Canadian violinist and music educator.  Born in Montreal, Boucher was the son of Canadian publisher and musician Adélard Joseph Boucher and the brother of conductor Joseph-Arthur Boucher.  His initial violin studies were with Jules Hone and Frantz Jehin-Prume.  In 1876 he went to Europe to study at the Royal Conservatory of Liège with Lambert Massart.  After returning to Canada, he had a triumphany success in Montreal performing Felix Mendelssohn's "Violin Concerto in E minor, Op. 64" in 1881.  In 1882 he and his father established a successful music store in Ottawa.  That same year he began playing first violin in a string quartet and working as a teacher.  In 1887 he joined the faculty of the Toronto Conservatory of Music.  He taught concurrently at the Toronto College of Music beginning in 1889.  He was a soloist with the Toronto Philharmonic Society in 1893 where he had success performing Max Bruch's "Violin Concerto No. 1".  In 1894 he emigrated to the United States.  In 1906 he joined the faculty of the Kansas City Conservatory of Music, where he taught through 1923.  His wife taught piano at the conservatory and his daughter was later a singing teacher at the school.  He died in Kansas City. The Violin Concerto in A major, P. 49 ("Concerto per Violino in La Maggiore") is Ottorino Respighi's first violin concerto, which was left unfinished by the composer in 1903, and then completed by Salvatore Di Vittorio in 2009. The Violin Concerto No. 3 in E major was composed by Niccolò Paganini in 1826.  On 12 December 1826, Paganini wrote from Naples to his friend L. G. Germi that, having recently completed his Second Violin Concerto, he had now "finished orchestrating a third with a Polacca", and added: "I would like to try these concertos out on my own countrymen before producing them in Vienna, London and Paris."  In the event, the Third Violin Concerto does not seem to have been premiered until July 1828 in Vienna.  Since Paganini's death in 1840 concerto wasn't performed for more than a century until it was eventually rediscovered in the late 1960s and first recorded and publically performed by Henryk Szeryng in 1971. The Violin Concerto No.5 in A minor, Op. 37, by Henri Vieuxtemps was published in 1861 and composed 1858–1859.  This remains Vieuxtemps' most popular violin concerto, having been recorded by many great violinists, including Jascha Heifetz, Pinchas Zukerman, Itzhak Perlman, Cho-Liang Lin and Kyung-wha Chung.  Auer (1925, p. 75) writes that the concerto had been "practically forgotten" but if played as its composer intended, "will not fail to impress the majority of its auditors".  The second movement borrows from "Où peut-on être mieux qu'au sein de sa famille?"  in Grétry's opera "Lucile". Bohuslav Martinů's Violin Concerto No. 2 in G minor, H. 293 was composed between February and April 1943 between his first two symphonies and premiered on December 31 by Mischa Elman and the Boston Symphony conducted by Sergei Koussevitzky.  Elman requested the concerto following the premiere of the dramatic Symphony No. 1 by the same orchestra, impressed by the work.  It was referred as Martinů's only violin concerto until an earlier concerto which was thought to be lost appeared in 1968, nine years after the composer's death. Violin Concerto No. 1 may refer to any composers' first violin concerto, or to a composer's only violin concerto: Béla Bartók's Violin Concerto No. 2, BB 117 was written in 1937–38.  During the composer's life, it was known simply as his Violin Concerto.  (His other violin concerto, Violin Concerto No. 1, Sz.  36, BB 48a was written in the years 1907–1908, but only published in 1956, after the composer's death, as "Violin Concerto No. 1, Op.  posth.")
Answer: Pyotr Ilyich Tchaikovsky