General manager Marc Bergevin appointed assistant Dominique Ducharme as the interim head coach and named Alex Burrows, who was previously an assistant coach with the AHL's Laval Rocket, as an assistant on Ducharme's staff.
The move was made despite Montreal currently holding a playoff spot, as it is fourth in the North Division with a 9-5-4 record for 22 points.
Bergevin released the following statement regarding the decision:
"I would like to sincerely thank Claude and Kirk for their contributions to our team over the past five years during which we worked together. I have great respect for these two men whom I hold in high regard. In Dominique Ducharme, we see a very promising coach who will bring new life and new energy to our group. We feel that our team can achieve high standards and the time had come for a change."
Julien, 60, was in the midst of his eighth season as head coach of the Habs overall.
His head coaching career began in Montreal in 2002, and he was fired during the 2005-06 season in his third year on the job.
Julien went on to coach the New Jersey Devils and Boston Bruins before returning to Montreal's bench during the 2016-17 season.
While Julien led the Canadiens to the playoffs last season, they reached the postseason in just three of his eight campaigns with the team overall. They also won just two playoff series during that time.
His greatest success came during his 10-year stint in Boston, as he led the Bruins to seven playoff appearances, two Stanley Cup Finals and one Stanley Cup championship.
Overall, Julien owns a career NHL head coaching record of 667-445-10-152 over 19 seasons.
In Ducharme, the Canadiens are trying out a coach who has no NHL head coaching experience, but plenty of head coaching experience at a high level nonetheless.
Ducharme was the head coach of the QMJHL's Halifax Mooseheads for five seasons from 2011-12 through 2015-16 and then the QMJHL's Drummondville Voltigeurs for two seasons from 2016-17 through 2017-18.
The Joliette, Quebec, Canada, native went 255-158-37 overall and led his teams to six postseason appearances. That included a Memorial Cup win with Halifax in 2012-13, as he coached a team that featured future NHL superstar Nathan MacKinnon.
With Montreal, Ducharme will look to get the most out of the likes of potential young stars such as Nick Suzuki and Jesperi Kotkaniemi.