Leoš Janáček (1854 – 1928) was a Czech composer, musical theorist, folklorist, publicist and teacher. He was inspired by Moravian and other Slavic folk music to create an original, modern musical style.
In his early professional life he was dedicated largely to research of folk music, and early original musical output was influenced by contemporaries such as Antonín Dvořák. Later works demonstrate a synthesis of his early folk studies with an original compositional voice. His opera Jenůfa (premiered in 1904 in Brno and Prague in 1916) introduced Janáček to the international stage. Later works include the operas Káťa Kabanová and The Cunning Little Vixen, the Sinfonietta, the Glagolitic Mass, two string quartets, and other chamber works.