Although known for his guitar work with Marilyn Manson, David Lee Roth, Rob Halford and Rob Zombie, Requiem is the guitarist's fourth solo album and follows on the heels of 2007's The Devil Knows My Name, which was voted Best Shred Album of the Year in the 2008 Guitar World readers' poll.

Requiem continues John 5's exploration into macabre music, with each track title reflecting the name of torture devices, such as "Sounds of Impalement." Says John 5, “I find the macabre fascinating, it’s all over history. In researching the torture devices I heard music to describe each one.” Recorded in the middle of the night, all instruments on the album are performed by John 5 except for percussion, which is handled by Rob Zombie bandmate Tommy Clufetos.