UNCHAIN was formed in Kyoto in 1996. Later, they moved into Osaka and began playing live gigs there. They progressed musically and put out demo songs on compilation CDs and started to work on their mini album, with their guitarist now not just a support member. He joined the band for the production of the mini album "The Space of the Sense" which was released on June 8, 2005. They have released several mini-albums and three full-length albums since then.