The band has had multiple lineup changes since its inception, but is now rounded out by founder Chris Petersen, drummer Nick McCallister, keyboardist Diego Valadez, and guitarist Eric Meyers.
In an article from the December 2006 issue of Metal Maniacs magazine, Chris Petersen says he created the band name in reference to a J. R. R. Tolkien essay which stated that the two words cellar and door have an appealing sound when combined.
Cellador has toured across the United States, Canada and Mexico with bands such as Trivium, Bullet for My Valentine, All that Remains, Protest the Hero, The Human Abstract, The Sword, Behemoth, and Sonata Arctica.
Led by guitarist/songwriter Chris Petersen, the band held continuous auditions for the entirety of 2009–2012 and ultimately reformed with bass player James Pickett, drummer Nick Mccallister, keyboardist Diego Valadez, and guitarist Caleb Delaet.
They spent the entirety of the year establishing in the Colorado area, and playing one-off shows as guest openers for Havok, Into Eternity, Helloween, Shining, Vale of Pnath, Amaranthe, and others.