Anton Bruckner (1824 – 1896) was an Austrian composer known primarily for his symphonies, masses, and motets. His symphonies are often considered emblematic of the final stage of Austro-German Romanticism because of their rich harmonic language, complex polyphony, and considerable length. Bruckner's compositions helped to define contemporary musical radicalism, owing to their dissonances, unprepared modulations, and roving harmonies.

Unlike other radicals, such as Wagner or Hugo Wolf who fit the enfant terrible mold, Bruckner showed extreme humility before other musicians, Wagner in particular. This apparent dichotomy between Bruckner the man and Bruckner the composer hampers efforts to describe his life in a way that gives a straightforward context for his music.

His works, the symphonies in particular, have detractors (especially in English-speaking countries) who point to their large size, their use of repetition, Bruckner's propensity to revise many of his works, often with the assistance of colleagues, and his apparent indecision about which versions he preferred.