Jeremy Colliton, formerly the head coach of the AHL's Rockford IceHogs, has been named his replacement. The 33-year-old is now the youngest coach in the NHL, while Quenneville's run as the league's longest-tenured bench boss has come to an abrupt end.
Along with Quenneville, assistants Kevin Dineen and Ulf Samuelsson were also fired.
The Blackhawks have gone 3-6-1 in their last 10 games and currently sit two points out of a wildcard spot in the Western Conference. Their latest loss came Saturday evening, when the Calgary Flames scored four unanswered goals to erase Chicago's 3-1 lead.
Quenneville turned the Blackhawks into a dynasty after being hired in 2008, winning three Stanley Cups from 2010 to 2015 along with three Central Division titles and a Presidents' Trophy in 2013. His overall record with the club was 446-243-93.
He signed a three-year extension with the Blackhawks in 2016 and is owed the remainder of this year's salary as well as $6 million for next season, according to TSN's Pierre LeBrun.