German composer and musical theorist, one of the most influential figures of 19th-century Europe.
Born May 22, 1813, in Leipzig, Wagner studied at the University of Leipzig. Between 1833 and 1839 he worked at provincial opera houses in Würzburg, Magdeburg, Königsberg, and Riga. During these years he wrote the operas Die Feen (The Fairies, 1833) and Das Liebesverbot (The Forbidden Love, 1836) and several orchestral works. In 1836, while at Königsberg, Wagner married the actor Minna Planer (1809-66). At Riga he completed the libretto and the first two acts of his first important opera, Rienzi.
In 1839 Wagner sailed to London. During the tempestuous voyage across the North Sea, he conceived the idea for his second major opera, Der fliegende Holländer (The Flying Dutchman, completed in 1841). After eight days in London, he traveled to France, settling eventually in Paris, where he became acquainted with the music of Hector Berlioz. He remained in Paris until April 1842, at times reduced to the direst poverty. On Oct. 20, 1842, Rienzi was produced at the Court Theater at Dresden, Germany. Its success led to the production of Der fliegende Holländer at Dresden on Jan. 2, 1843. In the same month Wagner moved to Dresden, where he became one of the conductors at the Court Theater.
Innovative Art.
Wagner's romantic opera Tannhäuser was produced at Dresden on Oct. 19, 1845. This work, with innovations in structure and technique, perplexed audiences accustomed to the conventional opera of the day and elicited a storm of adverse criticism. Nevertheless, Tannhäuser was produced at Weimar, Germany, three years later by the Hungarian composer Franz Liszt, who afterward became an enthusiastic proponent of Wagnerian music drama (see below). The meeting of Liszt and Wagner in 1848 resulted in a lifelong friendship. In the same year the romantic opera Lohengrin was completed, but the management of the Court Theater at Dresden, apprehensive of public and critical reaction to another work by the composer of Tannhäuser, declined to produce it. Liszt once more came to the rescue and produced Lohengrin at Weimar on Aug. 28, 1850.

A Political Radical
Wagner was an extreme radical in politics. He participated in the abortive Revolution of 1848 in Germany and, in consequence, was obliged to flee from his homeland, first to Paris, and then to Zürich. There he amplified the sketches, previously begun, for his famous tetralogy of music dramas, known collectively as Der Ring des Nibelungen, and based on the 12th-century Middle High German epic poem of the Nibelungenlied. The texts of the Nibelung dramas were written in reverse order. Finding that certain narrative episodes in Götterdämmerung (The Twilight of the Gods), the final work of the tetralogy, required elaboration and dramatic exposition to make the story altogether comprehensible, Wagner wrote the third part, Siegfried. Still not satisfied, however, he wrote Die Walküre and, as a further explanatory prelude, Das Rheingold. Wagner began work on the score of Das Rheingold in November 1853, completing it in May of the following year. By the end of December 1856, the score of Die Walküre was finished.
Meanwhile, in 1852, Wagner had made the acquaintance of the wealthy merchant Otto Wesendonck (1815-97) and his wife Mathilde (1828-1902). The former placed at the disposal of Wagner and Minna a small cottage, the Asyl (Ger., "Asylum"), on the Wesendonck estate near Zürich; this situation furnished the composer with the inspiration for some of his finest music. Close association between Wagner and Mathilde soon developed into love, which they were forced to renounce. Their romance eventually found expression, however, in Wagner's passionate score of Tristan und Isolde (1857-59), which is one of the longest and the most difficult to produce of all the Wagnerian music dramas. Its first performance was on June 10, 1865, at Munich, under the auspices of Louis II, king of Bavaria, who had become Wagner's patron. From this period also are the Wesendonck Lieder, settings for voice and orchestra or piano (1857-58) of five poems by Mathilde Wesendonck.
In 1861 the political ban against Wagner was lifted. Upon his return to Prussia the composer settled in Biebrich, where he began work on his only comic opera, Die Meistersinger von Nürnberg, completed in 1867. The work was produced on June 21, 1868, at Munich, where in 1869 and 1870 Das Rheingold and Die Walküre also were given by command of the king.
Immediately after the production of Die Meistersinger Wagner resumed work on the score of Siegfried, completing it in February 1871. At the same time he began the composition of Götterdämmerung. Meanwhile, on Aug. 25, 1870, the composer, who had been separated from his first wife for nine years, married Cosima von Bülow (1837-1930), the divorced wife of the pianist and conductor Hans Guido von Bülow and the daughter of Liszt. Wagner's orchestral work Siegfried Idyll (1870) was written for Cosima. In the summer of 1872, Wagner composed the last part of Der Ring des Nibelungen, and by November 1874, orchestration of Götterdämmerung had been completed. On Aug. 13-17, 1876, the premiere performance of the whole tetralogy took place at the Festspielhaus, a theater in Bayreuth designed and constructed especially for the presentation of Wagnerian music dramas. In 1877 Wagner began work on Parsifal, based on legends of the Holy Grail. The last of the Wagnerian music dramas, Parsifal was produced for the first time on July 26, 1882.
In 1882 the composer's health began to fail. Thinking he might benefit from a change of climate, Wagner rented the Palazzo Vendramin on the Grand Canal in Venice; he died there suddenly on February 13 of the following year. Five days later his body was interred in the mausoleum of his Bayreuth villa.

Theoretical Works
Wagner highly influenced late 19th-century thought, not only in the arts, but also in political issues such as nationalism and social idealism. In Oper und Drama (1850-51) he set forth his vision of a revolutionary kind of stage work, integrating dramatic, visual, and musical elements into a wholly unified work of art, or Gesamtkunstwerk. His other theoretical writings include Über deutsches Musikwesen (On German Music, 1840), Das Kunstwerk der Zukunft (The Art Work of the Future, 1849), Religion und Kunst (Religion and Art, 1880), Über das Dirigieren (On Conducting, 1869), Über die Anwendung der Musik auf das Drama (On the Application of Music to the Drama, 1879), and Eine Mitteilung an meine Freunde (A Communication to My Friends, 1851). Wagner also wrote an autobiography, My Life (1865-80; trans. 1911).

Criticism
Wagner's reputation is based on his musical creations, which represent the highest expression of romanticism in European music, and also on the revolution he effected in both the theory and practice of operatic composition. He began his career as a composer of opera in the conventional manner, but by the time he started work on Der Ring des Nibelungen he was creating an entirely new musico-dramatic form. The true line of development of the Wagnerian music drama is from Greek drama (on which Wagner deliberately modeled his texts) through the dramas of Shakespeare and the German poet Johann Christoph Friedrich von Schiller. On the purely musical side, because of its architectural structures, its lineal evolution is from Johann Sebastian Bach through Ludwig van Beethoven. In his treatment of harmony, Wagner pushed the traditional system of tonality to its limits, breaking down the conventions that gave keys and chord relationships their identity, and leading inevitably to 20th-century atonality.
Pre-Wagnerian opera had become little more than a succession of stereotyped arias, recitatives, duets, interludes, and finales. A fundamental principle of the music drama is the subservience of all the arts involved, including music, to the dramatic needs of the story. By means of the leitmotiv, or leading motive, a continuous thematic development is achieved. The complex evolutions of each leitmotiv and its intertwinings with others underline the emotional meaning of the drama. The increased dramatic unity of post-Wagnerian opera was one consequence of the tremendous influence of his art on every form of music.