ullmuzzler was a side project conceived by vocalist James LaBrie (of Dream Theater) and Terry Brown (Producer for Rush during the 1970s). Working with special guests Mike Keneally (guitar), Mike Mangini (drums), Matt Guillory (of Dali's Dilemma; keyboard/piano), Trent Gardner (of Magellan/of Explorers Club), Brian Beller (bass) and members of Shadow Gallery the idea of Mullmuzzler was born. Their influences stem as far back as Zeppelin, Styx and Queen in the classic rock way of doing things. It was designed to be a one off solo effort that was both rhythmic and digestible but ended off expanding into more releases. The record company would not allow LaBrie to use his own name, so he created the name of MullMuzzler. LaBrie coined the word "MullMuzzler" and defined it as: to gag or silence an individual's thought before it can be expressed in any manner. For the followup, he negotiated the right to use his name although still unable to simply credit it as his solo album.
Unlike many releases of this era, their 1999 debut, Keep It To Yourself, had something to say; it spoke of James LaBrie's personal influences and ideas. The cover image of one man shouting another's ear off, quite literally, was not only creative but also inspiring and sums up the hard rock music of today. It did not receive as heavy media exposure as they expected which was a shame. The album, however, ended off being one of the most critically acclaimed for the record label 'Magna Carta', and would lead to another Mullmuzzler follow-up simply called 2 (2001) with all the same "guest stars", and Mike Borkosky joining on guitars. This album was even more artsy and took Progressive metal to its ultimate extreme. An album about life and relationships, it was a far cry from LaBrie's work with Dream Theater; it received no less acclaim. The project ended off continuing because the releases of Elements of Persuasion (2005), Prime Cuts (2008), Static Impulse (2010), Impermanent Resonance (2013) and I Will Not Break (2014) would result. All recordings since 2005 featured the line up of James LaBrie (vocals), Matt Guillory (keyboards/vocals) and Marco Sfogli (guitar) with Peter Wildoer (drums/harsh vocals) and Ray Riendeau (bass) who joined in 2010.