Lupus Dei is the second studio album by German power metal band Powerwolf. In addition to recording at Woodhouse Studios, Germany, the band recorded some parts of the album in the 12th-century Deutschherrenkapelle chapel in Saarbrücken. The band also used a 30-piece choir on the songs "In Blood We Trust" and "Lupus Dei". In a May 2007 interview with Lords of Metal, Matthew Greywolf talked about the story in Lupus Dei:Well, generally 'Lupus Dei' is focussed on parables taken out of the Bible and set in context to our passion for metal. Finally it had turned out being a real concept album with the wolf himself as the protagonist. In the Introduction to the album he loses faith in good and descends to the evil. He doesn't believe in anything but blood anymore – but during the album he realizes the light of God step by step and finally in the title track he experiences God.

Powerwolf is a German power metal band founded in 2003 in Saarbrücken by members of Red Aim. The band consists of vocalist Karsten Brill as "Attila Dorn", lead guitarist Benjamin Buss as "Matthew Greywolf", bassist/rhythm guitarist David Vogt as "Charles Greywolf", keyboardist Christian Jost as "Falk Maria Schlegel" and drummer Roel van Helden. The group uses religious themes and images, contrary to traditional power metal music, as well as corpse paint, gothic-tinged compositions and songs about werewolf and vampire legends.