The Piano Concerto No. 21 in C major, K. 467, was completed on March 9, 1785 by Wolfgang Amadeus Mozart, four weeks after the completion of the previous D minor concerto, K. 466.

There are three movements.

The opening movement begins quietly with a march figure, but quickly moves to a more lyrical melody interspersed with a fanfare in the winds. The music grows abruptly in volume, with the violins taking up the principal melody over the march theme, which is now played by the brass. This uplifting theme transitions to a brief, quieter interlude distinguished by a sighing motif in the brass. The march returns, eventually transitioning to the entrance of the soloist. The soloist plays a brief Eingang (a type of abbreviated Cadenza) before resolving to a trill on the dominant G while the strings play the march in C major. The piano then introduces new material in C major and begins transitioning to the dominant key of G major. Immediately after an orchestral cadence finally announces the arrival of the dominant, the music abruptly shifts to G minor in a passage that is reminiscent of the main theme of the Symphony No. 40 in that key. A series of rising and falling chromatic scales then transition the music to the true second theme of the piece, an ebullient G major theme which Mozart had previously used in his Third Horn Concerto. The usual development and recapitulation follow. There is a cadenza at the end of the movement, although Mozart's original has been lost.

Wolfgang Amadeus Mozart (German: [ˈvɔlfɡaŋ amaˈdeus ˈmoːtsaʁt], English see fn.), baptismal name Johannes Chrysostomus Wolfgangus Theophilus Mozart (27 January 1756 – 5 December 1791), was a prolific and influential composer of the Classical era. He composed over 600 works, many acknowledged as pinnacles of symphonic, concertante, chamber, operatic, and choral music. He is among the most enduringly popular of classical composers.

Mozart showed prodigious ability from his earliest childhood in Salzburg. Already competent on keyboard and violin, he composed from the age of five and performed before European royalty. At 17, he was engaged as a court musician in Salzburg, but grew restless and travelled in search of a better position, always composing abundantly. While visiting Vienna in 1781, he was dismissed from his Salzburg position. He chose to stay in the capital, where he achieved fame but little financial security. During his final years in Vienna, he composed many of his best-known symphonies, concertos, and operas, and portions of the Requiem, which was largely unfinished at the time of his death. The circumstances of his early death have been much mythologized. He was survived by his wife Constanze and two sons.

Elvira Madigan (4 December 1867 – 20 July 1889) was a Danish tightrope walker and trick rider, whose illicit affair and dramatic death at the hands of her lover were the subject of the Swedish film of 1967.

She was born Hedvig Antoinette Isabella Eleonore Jensen in Flensburg in northern Germany. Her mother was a Norwegian circus performer and her father a Danish stablemaster. Her mother later lived with the American circus manager John Madigan.

While performing in Sweden with her stepfather's circus, she met a Swedish cavalry officer, Lieutenant Count Bengt Edvard Sixten Sparre (27 September 1854 – 20 July 1889). Sparre and Madigan fell in love, but their love was impossible, partly due to the fact that Sparre was married and the father of two children. After exchanging love letters for a year, they ran away together to Denmark in June 1889, where they spent about a month. When they ran out of money, they packed a picnic basket, went out to the Nørreskov ("North forest") on the island Tåsinge, Denmark, and had a last meal, after which Sparre shot Madigan and himself with his service revolver. Madigan was 21 years old and Sparre 35 years old.

Keith Jarrett (born May 8, 1945, in Allentown, Pennsylvania) is an American pianist and composer who performs both jazz and classical music.

Jarrett started his career with Art Blakey, moving on to play with Charles Lloyd and Miles Davis. Since the early 1970s he has enjoyed a great deal of success in jazz, jazz fusion, and classical music; as a group leader and a solo performer. His improvisations draw not only from the traditions of jazz, but from other genres as well, especially Western classical music, gospel, blues, and ethnic folk music.

In 2003, Jarrett received the Polar Music Prize, the first (and to this day only) recipient not to share the prize with a co-recipient, and in 2004 he received the Léonie Sonning Music Prize.

In 2008, he was inducted into the Down Beat Hall of Fame in the magazine's 73rd Annual Readers' Poll.

Jarrett grew up in suburban Allentown, Pennsylvania, with significant early exposure to music. He possessed absolute pitch, and he displayed prodigious musical talents as a young child. He began piano lessons just before his third birthday, and at age five he appeared on a TV talent program hosted by the swing bandleader Paul Whiteman. The young Jarrett gave his first formal piano recital at the age of seven, playing works by composers including Mozart, Bach, Beethoven, and Saint-Saëns, and ending with two of his own compositions. Encouraged especially by his mother, Jarrett took intensive classical piano lessons with a series of teachers, including Eleanor Sokoloff of the Curtis Institute.

Wilhelm Walter Friedrich Kempff (25 November 1895 – 23 May 1991) was a German pianist and composer. Although his repertory included Bach, Liszt, Chopin, Schumann, and Brahms, Kempff was particularly well known for his interpretations of the music of Ludwig van Beethoven and Franz Schubert, both of whose complete sonatas he also recorded. He is considered to have been one of the chief exponents of the Germanic tradition during the 20th century.

Kempff was born in Jüterbog, Brandenburg, in 1895. He grew up in nearby Potsdam where his father was a royal music director and organist at St. Nicolai Church. His grandfather was also an organist and his brother Georg became director of church music at the University of Erlangen. Kempff studied music at first at the Berlin Hochschule für Musik at the age of nine after receiving lessons from his father at a younger age. Whilst there he studied composition with Robert Kahn and piano with Karl Heinrich Barth (with whom Arthur Rubinstein also studied). In 1914 Kempff moved on to study at the Viktoria gymnasium in Potsdam before returning to Berlin to finish his training.