Compared with the custom of the time, they had a free upbringing - indeed so free that some people thought it went a bit too far when one child after the other was sent to Paris to study. In 1878 it was Gerhard's turn. In Paris, he studied cello under Auguste Franchomme and music theory under Augustin Savard. His interest in theory and composition gradually replaced his love of the cello and when he returned to Norway in 1884 he had already completed several compositions, including Elegi and Fantasistykke, both for cello and piano.
In 1866 Jules Massenet became his composition teacher at the Paris Conservatoire and Schjelderup demonstrated a great talent for instrumentation. It was in Paris he first became acquainted with the scores of Wagner's operas. Obsessed with Wagner's orchestration and his innovative musical-dramatic ideas, Schjelderup went to Germany to experience his operas on stage. From then on he was sure that his future would be in the operatic genre. His first effort was Østenfor sol og vestenfor måne (East of the Sun and West of the Moon, 1888-90) based on a text by Kristofer Janson. Favourable reviews by Hermann Levi and Felix Mottl strengthened his belief in his future as an opera composer and he started writing Sonntagsmorgen, which was accepted for performance at the Munich Hoftheater (1893). Conductor Hermann Levi and the rest of the performers liked it and the audience applauded but the critics were disparaging and wrote of “hair-raising cacophonies”.
His next work was Bruderovet, or Macht der Liebe, which was the original German title (1892). The opera was on the programme for the Dresden opera but due to continual delays and intrigues it was not performed until 1900 - in Prague under the title Norwegische Hochzeit. After that operas appeared one after the other: Vårnatt (Spring Night, 1905), first performed in Dresden in 1908, recorded in 1980, later extended by two acts to Liebesnäcbte (Nights of Love, 1921), first performed in Lübeck, 1934; Sturmvogel (Storm Bird), started at the end of the 1890s, first performed in Schwerin in 1926; Den røde Pimpernell (The Scarlet Pimpernel, 1912-13), Et folk i nød (A People in Need), begun in the 1890s and completed in 1893, and Sampo Lappelil (1897). He wrote the librettos himself.
It is not difficult to find Wagnerian elements in his operas. He often used the leitmotiv technique, and the orchestra is clearly as important as the singing in carrying the dramatic characterisation and development. At the same time, however, the music is influenced by Schjelderup's studies in France, with refined instrumentation and often a fluent elegance that is not immediately associated with the Wagnerian style.
Today, Schjelderup is remembered primarily for his musical drama but he also wrote many other works: two symphonies, orchestral works such as Sommernatt på fjorden (Summer Night on the Fjord) and Soloppgang over Himalaya (Sunrise over the Himalayas), a string quartet, a piano trio, the monologue Die Blinde (to a text by Rainer Maria Rilke) and a long series of songs. He wrote several articles on foreign music and the musical scene for Norwegian newspapers and magazines, biographies of Grieg (1903) and Wagner (1907, with Walter Niemann), and he was responsible for the first, and for many years the only, Norwegian history of music, published in 1921 with O. M. Sandvik.
Although he lived outside Norway for most of his productive life, he was also highly interested in ensuring that Norwegian composers had working conditions that would allow them to concentrate on their creative activities. He was one of the founders of the Norwegian Society of Composers in 1917 and was also its first chairman (1917-20). Schjelderup died at his home in Benediktbeuern, Bavaria, in 1933.