Hermann Nitsch (1938, Vienna) is one of the founders of Vienna Actionism, known for his performances and works reminiscent of the practices of sacrifice.

Nitsch studied at the Wiener Graphische Lehr-und Versuchanstalt. Expressionism and religious figurative motifs influenced his early works, and in the early 1960s, he moved towards Art Informel.

In the 1950s, Nitsch started the Orgien Mysterien Theater performance series, which had over 100 performances to date. The performances include the motifs of ritualistic sacrifice, often including nudity, blood or animal flesh. It is a multisensory experience including as well as music, dancing and several participants. Nitsch's painting works connect to his performances, and include stained clothes, bandages, splatters of paint etc. He is also a composer (symphonies, organ concerts), and set designer. The majority of Nitsch's non-performance works fall into the categories of canvases painted in blood-red shades (some with added cloth pieces), tables with ritualistic objects (medicinal utensils, religious paraphernalia, various vessels holding fluids), photographs of the actions, sketches of the actions, and video-documentation of the actions.

He is one of the founders of Vienna Actionism, a loosely connected group of artists including also Günter Brus, Otto Muehl, and Rudolf Schwarzkogler. The Vienna Actionists were confrontational artists, and the movement is characterised by a violent, radical, and explicit form of performance art. They were active between 1960 and 1971. The first action they did together was called Die Blutorgel and was presented in 1962 in Vienna. They continued to create independently from the early 1970s onwards.

In 1971 Nitsch acquired the Prinzendorf Castle in Lower Austria from the Catholic Church, where now he can perform his large-scale performances and music works.