NOTE: NBC Chicago will offer a live stream of the Blackhawks' press conference at 3 p.m. CT Tuesday right here.
Quenneville, who is in his 11th season with the team, joined the Blackhawks in 2008 and led the team to three Stanley Cup championships. He is the second-winningest head coach in team history, and has the second-most wins of any coach in NHL history.
Colliton, 33, is now the NHL's youngest head coach. He was 12 games into his second season with the Rockford IceHogs of the American Hockey League after being named IceHogs head coach in May 2017 - his first coaching job in North America.
Prior to joining the Hawks, Colliton spent four seasons as the head coach of Mora IK in Sweden.
The team also parted ways with assistant coaches Kevin Dineen and Ulf Samuelsson, and hired Barry Smith as an assistant to Colliton.
The rest of the staff will remain with the team, according to officials.
“The Chicago Blackhawks front office has made a decision to release Joel Quenneville from his head coaching duties, doing so with my full support," Hawks Chairman Rocky Wirtz said in a statement. "As Chicago Blackhawks fans have seen over the last decade, this organization no longer shies away from making tough decisions or ones based on emotion. Those days are long behind us. Of course, Joel’s was difficult, as it should have been. During his tenure as head coach to the Chicago Blackhawks, Joel brought the city of Chicago and our fans three Stanley Cups and an incredible era of hockey. When Joel was originally hired into our 2008 season, we had great hope for his potential to take the team to new levels. He went beyond what anyone expected. As difficult as that decision in 2008 was, this one was tougher. But as we look to a future history not yet defined, we believe the change we made today, will provide the Chicago Blackhawks a critical element in achieving our goals of Championships in the future, including this season. I wish Joel and his family well and thank him for his incredible leadership and results. Nothing will ever take away the success he brought our franchise, our fans and my family. Joel will forever be etched into the most memorable era in Chicago Blackhawk hockey. And for that, we will always be connected and always eternally grateful.”
Check back for more on this developing story.