Crystal Castles consists of producer Ethan Kath and vocalist Alice Glass. They are named after the lyrics “The fate of the world is safe in Crystal Castles” and “Crystal Castles, the source of all power” both from the theme song for She-Ra’s fortress. Ethan Kath formed the band alone in December 2003, in Toronto, Canada. In April 2005, Glass recorded vocals over five original instrumentals by Kath. The band’s first single Alice Practice was actually a microphone test by Glass. She was not aware that the recording existed until London UK’s Merok Records asked to release the track on vinyl. The release sold out instantly. NME Magazine has included their debut album in their “Top 50 Albums of the Decade” list at #39.

Crystal Castles are known not only for their own efforts as a band, but also for commissioned remixes for number of groups, including Hunting For Witches by Bloc Party, and Atlantis To Interzone” by friends and label mates, Klaxons.

In mid-2008, Crystal Castles were involved in two controversies related to artwork permissions and samples in their earliest unreleased songs. Crystal Castles used Trevor Brown’s artwork (depicting a black-eyed Madonna) without permission.

In one of Kath’s earliest, unreleased demos, he incorporated a sample without permission. The track, “Insectica (CC vs Lo-Bat Version)”, uses clips chopped out of a song by Lo-bat called “My Little Droid Needs a Hand”, released under a Creative Commons license. Another track called “Love And Caring”, samples the kick and snare from Covox’s “Sunday”.