German music project led by producer Frank Peterson. Gregorian performs popular rock and pop songs based on Gregorian chants.
In the first album, Sadisfaction Gregorian performed his songs composed by Frank Peterson and The Sisters of Oz, but in later ones he covered songs by other authors.
Originally, Gregorian was conceived as a more pop-oriented group in the vein of Enigma. Under this concept, Peterson together with Matthias Meissner and Thomas Schwarz, recorded the 1991 album Sadisfaction, with lead vocals provided by The Sisters of Oz: Susana Espelleta (Peterson's wife at the time) and Birgit Freud. However, this was the only album by the trio in that style.
In 1998, Peterson and his team of Jan-Eric Kohrs, Michael Soltau and Carsten Heusmann re-invented the project to perform popular songs in the Gregorian style. The criteria for song selection were strict; in order to be considered, a song needed to be translatable into the 7-tone scale. For each album, songs were carefully chosen in addition to original songs written by Jan-Eric Kohrs, Amelia Brightman and Carsten Heussman. Twelve vocalists - previously acclaimed session and choir singers - were then hired to record the tracks.
Each Gregorian album was initially digitally tracked at Nemo Studios, Peterson's Hamburg studio. The vocalists then record their parts in a church atmosphere with dimmed lights and candles, in order to escape what Peterson referred to in a 2001 interview as the "cold and technical" studio atmosphere.
The concept proved to be successful, and the group proceeded to record several more albums in the same style as Masters of Chant. Known as the ten "Chapters", said album releases primarily featured covers of well-known or popular songs (ex. Phil Collins' "In the Air Tonight", Alphaville's "Forever Young"; Celine Dion's "My Heart Will Go On", etc.) done in the group's chant-inspired style, though occasionally the group would release original compositions as well. Their 2004 album, The Dark Side, was a slight departure from the others, featuring a darker repertoire; similarly, the group released themed albums such as the Christmas-themed Christmas Chants, another dark-repertoire album with The Dark Side of the Chant (2010), and the themed Epic Chants (2012). In 2005, The Masterpieces, a compilation album with a live DVD, was released.