1866 in music
| List of years in music | 
|---|
| (table) | 
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Events
- January – Gabriel Fauré becomes organist at the Church of Saint-Sauveur, at Rennes in Brittany.[1]
 - March–December – Pyotr Ilyich Tchaikovsky writes his Symphony No. 1, Winter Daydreams.
 - May 30 – Bedřich Smetana's opera The Bartered Bride (Prodana Nevesta) debuts at the Provisional Theatre (Prague).
 - August – Sir William Sterndale Bennett becomes Principal of the Royal Academy of Music in London.[2]
 - August 4 – First performance of Gabriel Fauré's Cantique de Jean Racine.
 - August 9 – Marie Trautmann marries fellow musician Alfred Jaëll.
 - October 21 – Jacques Offenbach's operetta La Vie parisienne debuts in Paris at the Théâtre du Palais Royale.
 - November 17 – Ambroise Thomas's opera Mignon debuts in Paris at the Opéra-Comique.
 - Theodore Thomas conducts the New York Philharmonic in the American premiere of the Prelude to Act 1 of Wagner's Tristan und Isolde.
 - Mily Balakirev publishes his Collection of Russian Folksongs, including "The Song of the Volga Boatmen".
 - Georges Bizet completes the opera La jolie fille de Perth; it is premiered the following year.
 - Brahms completes all but the fifth movement of the A German Requiem
 
Published popular music
- "Beautiful River"
 - "Come Back To Erin" w.m. Claribel
 - "Father's a Drunkard and Mother Is Dead" w. Stella m. Mrs. E. A. Parkhurst
 - "We Parted By The River" w.m. William Shakespeare Hays
 - "When You and I Were Young, Maggie" by James A. Butterfield & George Washington Johnson
 - "Write Me A Letter Home" w.m. Will S. Hays
 - "You Naughty, Naughty Men" (in The Black Crook) w. T. Kennick m. G. Bickwell
 
Classical music
- Felix Draeseke – Fantasie on Themes from Boieldieus "Weisse Dame"
 - Johann Gottfried Piefke – Königgrätzer Marsch
 - Amilcare Ponchielli – Concerto for Trumpet in F major
 - Arthur Sullivan – Irish Symphony
 - Franz von Suppé - Light Cavalry Overture
 - Pyotr Ilyich Tchaikovsky - Symphony No. 1 "Winter Dreams"
 
- Karel Miry
- Maria van Boergondië (opera in 4 acts, libretto by N. Destanberg, premiered on August 28 in Ghent)
 - De Keizer bij de Boeren (opera in 1 act, libretto by N. Destanberg, premiered on October 29 in Ghent)
 - De occasie maakt den dief (opera in 1 act, libretto by N. Destanberg, premiered on December 24 in Ghent)
 
 - Bedřich Smetana- The Bartered Bride
 - Franz von Suppé – Leichte Kavallerie
 
- La Belle Hélène (Lyrics: Henri Meilhac & Ludovic Halévy Music: Jacques Offenbach) London production opened at the Adelphi Theatre on June 30
 - The Black Crook – the first "book musical". Broadway production opened at Niblo's Garden on September 12 and ran for 474 performances
 
Births
- January 13 – Vasily Kalinnikov, composer (d. 1901)
 - March 10 – Amanda Aldridge, opera singer, teacher and composer (d. 1956)
 - April 1 – Ferruccio Busoni, pianist, composer (d. 1924)
 - April 13 – Carl Valentin Wunderle, violinist (d. 1944)
 - May 17 – Erik Satie, composer (d. 1925)
 - June 15 – Charles Wood, composer (d. 1926)
 - June 29 – George Frederick Boyle, composer (d. 1948)
 - July 13 – La Goulue, can-can dancer (d. 1929)
 - July 23 – Francesco Cilea, composer (d. 1950)
 - September 26 – George H. Clutsam, pianist, composer and writer (d. 1951)
 - November 7 – Paul Lincke, composer (d. 1946)
 - date unknown
- Annibale Fagnola, violin maker (d. 1939)
 - Dorothea Ruggles-Brise, née Stewart-Murray, collector of traditional Scottish music (d. 1937)
 
 
Deaths
- January 25 – Minna Wagner, estranged wife of Richard Wagner, 56 (heart attack)
 - February 6 – Anna Liszt, pianist and mother of Franz Liszt, 77
 - March 20 – Rikard Nordraak, composer, 21 (tuberculosis)
 - July 25 – Aloys Schmitt, composer, pianist and music teacher, 77
 - October 2 – Adam Darr, guitarist, singer and composer, 55 (suicide by drowning)
 - November 26 – Adrien-Francois Servais, cellist, 59
 - November 29 – Sophie Löwe, operatic soprano, 51
 - December 1 – Jules Demersseman, flautist and composer, 33 (tuberculosis)
 - December 3 – Jan Kalivoda, violinist, conductor and composer, 65