MCMXC a.D. is the debut studio album by the German musical project Enigma, led by Romanian-German musician Michael Cretu. It was released in Europe by Virgin Records on 3 December 1990, and in the United States by Charisma Records on 12 February 1991. Cretu became fascinated with mixing archaic sounds with modern music after producing German pop singer Sandra's song "Everlasting Love", for which he experimented with Gregorian chant. Following Michael Cretu and Sandra's marriage in 1988, Michael developed the idea of the musical project Enigma and recorded the album over the course of eight months in 1990 at A.R.T. Studios. MCMXC a.D. combines new-age music with dance rhythms, as well as combining themes of religion and Gregorian chant with sexuality, for which the album received generally positive reviews from music critics. The Gregorian chant was taken from recordings by Capella Antiqua München, which resulted in the Munich-based choir's label, Polydor Germany suing Cretu and Virgin Records for infringing on its "right of personality". The case was dropped after Cretu agreed to pay compensation. Commercially, MCMXC a.D. became a worldwide success, reaching the top 10 on record charts in 10 countries, including charting at number six in the United States, staying on the country's Billboard 200 chart for 282 weeks. It was certified quadruple platinum in the US by the Recording Industry Association of America (RIAA). Four singles from the album were released: "Sadeness (Part I)", "Mea Culpa (Part II)", "Principles of Lust", and "The Rivers of Belief". The lead single topped charts worldwide. Background and release In 1987, Michael Cretu worked with Sandra on her song "Everlasting Love". Cretu experimented with Gregorian chant while working on the song with Sandra, and the chants appeared at the beginning of her song. He would become fascinated with incorporating archaic sounds into contemporary songs. Michael Cretu married Sandra in 1988 and came up with the idea of a new-age musical project, which would become known as "Enigma". MCMXC a.D. was recorded in 1990 in eight months at A.R.T. Studios, Cretu's studio located on the Spanish island of Ibiza. Cretu conceived the album as one continuous song; his philosophy when creating it was, "Contrary to the usual record-company philosophy, people are open-minded and starved for something unique." Cretu produced MCMXC a.D., with creative input from Frank Peterson and Fabrice Cuitad. The first song recorded for the album was "Sadeness (Part I)". After making