Gustav Mahler (German: [ˈɡʊstaf ˈmaːlɐ]; 7 July 1860 – 18 May 1911) was a late-Romantic composer and one of the leading conductors of his generation. He was born to a Jewish family in the village of Kalischt in Bohemia, in what was then the Austrian Empire, now Kaliště in the Czech Republic. His family later moved to nearby Iglau (now Jihlava), where Mahler grew up.

As a composer, Mahler acted as a bridge between the 19th-century Austro-German tradition and the modernism of the early 20th century. While in his lifetime his status as a conductor was established beyond question, his own music gained wide popularity only after periods of relative neglect which included a ban on its performance in much of Europe during the Nazi era. After 1945 the music was discovered and championed by a new generation of listeners; Mahler then became a frequently performed and recorded composer, a position he has sustained into the 21st century.