Leon Janácek (July 3, 1854 - August 12, 1928) was a Czech composer. He is particularly remembered for his orchestral piece Sinfonietta and for his operas, and is thought of as the greatest Czech composer of the early 20th century.
Janácek was born in Hukvaldy in Moravia, the son of a schoolmaster. As a boy, he sang in the choir of the monastery in Brno. He later went to Prague to study music, and made a living teaching music. He also conducted various amateur choirs. In 1881, he moved back to Brno, and founded the Organ School there, which was later to become the Brno Conservatory.
Janácek began composing in a relatively traditional romantic style, but after his opera Sárka (1881), his style began to change. He made a study of Moravian folk music and used elements of it in his own music. His opera Jenufa (1904) had very distinctive vocal melodies which closely followed the rhythm and pitch of normal Czech speech. This became a distinguishing feature of his vocal writing. When Jenufa was given in Prague in 1916, it was a great success, and brought Janácek real acclaim for the first time. He was 62 at the time, and began to compose the pieces he is now best known for.
The operas Katya Kabanova (1921), The Cunning Little Vixen (1924), The Makropulos Affair (1926) and From the House of the Dead (premiered in 1930, after his death) are regarded by many commentators as his finest works. The conductor Sir Charles Mackerras has become particularly closely associated with them.
Other well known pieces by Janácek include the Sinfonietta, the Glagolitic Mass (with words from a text in the Glagolitic alphabet) and his two string quartets. These pieces and the above mentioned four late operas were all written in the last decade of Janácek's life. He died in Ostrava.