Born in Drammen, Norway, Halvorsen was an accomplished violinist from a very early age and became a prominent figure in Norwegian musical life. He received his musical education in Kristiania (now Oslo) and Stockholm, and was a concertmaster in Bergen before joining the Leipzig Gewandhaus Orchestra. His best known work is the Bojarenes inntogsmarsj (Entry March of the Boyars) composed in 1893. Halvorsen was offered a post at the Bucharest Conservatory and while arriving at the decision of whether or not to accept he read about the city and about the entry of the Romanian Boyars into Bucharest in the eighteenth century. The scene almost "forced" the music out of him. Returning to Norway in 1893, he worked as conductor of the theatre orchestra at Den Nationale Scene in Bergen and of the Bergen Philharmonic Orchestra. He became concertmaster of the Bergen Philharmonic in 1885, and principal conductor in 1893. In 1899 he was appointed conductor of the orchestra at the newly-opened National Theatre in Kristiania, a position he held for 30 years until his retirement in 1929. Halvorsen's compositions were a development of the national romantic tradition exemplified by Edvard Grieg though written in a distinctive style marked by brilliant orchestration. Halvorsen married Grieg's niece, and orchestrated some of his piano works, such as a funeral march that was played at Grieg's funeral.