ISIS (original official capitalization) were a Los Angeles, California-based experimental / psychedelic / progressive metal band originally founded in Boston, Massachusetts in 1997, in the vein of Neurosis, Godspeed You! Black Emperor, and Godflesh.
On May 18, 2010, the band announced that they were disbanding. The statement said that they had "done everything we wanted to do, said everything we wanted to say," citing an agreement the band made early on to end before pushing "past the point of a dignified death." The final lineup reunited on October 13, 2018, to pay tribute to Caleb Scofield, and performed under the name Celestial due to the association of their namesake since disbanding.