Marianne G. Nielsen (soprano) graduated with a diploma from the Royal Danish Academy of Music in Copenhagen, where her teachers were professor Kirsten Buhl Mřller and Dorothy Irving. She has also studied Italian and French baroque interpretation with Jill Feldman in Paris.

In 1996 Marianne G. Nielsen was engaged by Barbara Thornton to record and perform Ordo Virtutum with SEQUENTIA KÖLN in this famous group's ongoing series of the complete works of Hildegard von Bingen. A CD was issued in 1998 on BMG Classics/Deutsche Harmonia Mundi, and Marianne G. Nielsen received acclaim for live appearances in this production at the Royal Albert Hall, London, and other major venues such as the Lincoln Center in New York City and St Paul's Cathedral in Melbourne, Australia.

Marianne G. Nielsen made her opera debut in Jerusalem in the year of 2000, singing the role of Amore in Gluck's Orfeo. Recently she has sung the title role in Johannes Fabricius and Danish composer Lars Bisgaard's three act cantata opera Silvia with music by J. S. Bach. A recording of this work was issued on CD.

In May 2002 and November 2003, Marianne G. Nielsen toured as a soloist in China and Hong Kong with her Hildegard repetoire and an Opera programme. In July 2004 she participated in St. Petersburg Baroque Festival.

Marianne G. Nielsen has also made concert appearances and recordings with leading Scandinavian early music ensembles including CONCERTO COPENHAGEN, CAPELLA HAFNIENSIS, CON STRUMENTI, MUSICA FICTA and WASA BAROCK.

Marianne G. Nielsen has toured as a soloist in most European countries as well as Australia, the United States, Russia and China, and has been heard in radio and television broadcasts on Danmarks Radio, the BBC (Henry Wood Promenade Concerts), Westdeutscher Rundfunk, Israeli TV1 and Radio France.