Wagner made a major contribution to the principles and practise of conducting. His essay On conducting (1869) advanced the earlier work of Hector Berlioz and proposed that conducting was a means by which a musical work could be re-interpreted, rather than simply a mechanism for achieving orchestral unison. The central European conducting tradition which followed Wagner's ideas includes artists such as Hans von Bulow, Arthur Nikisch, Wilhelm Furtwängler and Herbert von Karajan.
Wagner also made significant changes to the conditions under which operas were performed. It was Wagner who first demanded that the lights be dimmed during dramatic performances, and it was his theatre at Bayreuth which first made use of the sunken orchestra pit, which at Bayreuth entirely conceals the orchestra from the audience.
Wagner's concept of leitmotif and integrated musical expression has been a strong influence on many 20th century film scores, including such examples as Walt Disney's Snow White and the Seven Dwarves and John Williams' music for Star Wars. American producer Phil Spector with his "wall of sound" was strongly influenced by Wagner's music. Wagner also heavily influenced rock composer Jim Steinman and led him to create what he called Wagnerian Rock. The rock subgenre of heavy metal music also shows a Wagnerian influence with its strong paganistic stamp. In Germany Rammstein and Joachim Witt (his most famous albums are called Bayreuth for that reason) are both strongly influenced by Wagner's music. The movie "The Ring of the Nibelungs" drew both from historical sources as well as Wagner's work, and set a ratings record when aired as a two-part mini-series on German television. It was subsequently released in other countries under a variety of names, including "Dark Kingdom: The Dragon King" in the USA.
Wagner's influence on literature and philosophy is also significant. Friedrich Nietzsche was part of Wagner's inner circle during the early 1870s, and his first published work The Birth of Tragedy proposed Wagner's music as the Dionysian rebirth of European culture in opposition to Apollonian rationalist decadence. Nietzsche broke with Wagner following the first Bayreuth Festival, believing that Wagner's final phase represented a pandering to Christian pieties and a surrender to the new demagogic German Reich. In the twentieth century, W. H. Auden once called Wagner "perhaps the greatest genius that ever lived", while Thomas Mann and Marcel Proust were heavily influenced by him and discussed Wagner in their novels. He is discussed in some of the works of James Joyce although Joyce was known to detest him. Wagner is one of the main subjects of T. S. Eliot's The Waste Land, which contains lines from Tristan und Isolde and refers to The Ring and Parsifal. Charles Baudelaire, Stéphane Mallarmé and Paul Verlaine worshipped Wagner. Many of the ideas his music brought up, such as the association between love and death (or Eros and Thanatos) in Tristan, predated their investigation by Sigmund Freud.
Not all reaction to Wagner was positive. For a time, German musical life divided into two factions, Wagner's supporters and those of Johannes Brahms; the latter, with the support of the powerful critic Eduard Hanslick, championed traditional forms and led the conservative front against Wagnerian innovations. Even those who, like Debussy, opposed him ("that old poisoner"), could not deny Wagner's influence. Indeed, Debussy was one of many composers, including Tchaikovsky, who felt the need to break with Wagner precisely because his influence was so unmistakable and overwhelming. Others who resisted Wagner's influence included Gioachino Rossini ("Wagner has wonderful moments, and dreadful quarters of an hour"), though his own "Guillaume Tell," at over four hours, is comparable in length to Wagner's operas.