The 53-year-old replaces Bruce Cassidy, who was fired June 7 after six seasons. Boston (51-26-5) qualified for the Stanley Cup Playoffs in each of Cassidy's six seasons but hasn't advanced past the second round since a seven-game loss to the St. Louis Blues in the 2019 Cup Final.
"The Boston Bruins are pleased to introduce Jim Montgomery as the next head coach of the Boston Bruins and welcome Jim, his wife, Emily, and his children, JP, Colin, Ava and Olivia, to the city of Boston," Bruins general manager Don Sweeney said. "Jim has a winning history, and throughout the interview process he conveyed his ability to connect with all types of players while also demanding that his teams play with structure. We are excited for Jim to begin to make his imprint on our team."
Montgomery spent the past two seasons as an assistant for the Blues and helped them advance to the Western Conference Second Round this season, when they lost in six games to the Colorado Avalanche.
"'Monty' was a great member of our staff and I appreciate his time and efforts with our players," St. Louis coach Craig Berube told the Blues website. "This is well deserved and I wish him well with the Bruins."
Prior to that, Montgomery coached the Dallas Stars for two seasons before being fired Dec. 10, 2019 because of unprofessional conduct. He later said he had been receiving counseling for alcohol abuse and had checked himself into an in-patient residential program.
Montgomery was 61-43-10 for Dallas.
"Sometimes it takes an unbearable consequence in your life to happen to have an unbelievable breakthrough," Montgomery said when he was hired by the Blues on Sept 16, 2020. "I didn't know I was headed down the wrong path, and once I found out and you realize you do have a problem, it's time to get to work and try and fix it. It's over nine months now, I'm sober and I'm just very thankful for what happened because now I'm a much better person every day and obviously a better husband, father and son to the people I care about the most."
Montgomery was hired by the Stars after five seasons as coach at the University of Denver, where he won the NCAA championship in 2016-17. He also was named the Spencer Penrose National Coach of the Year the same season. As a player, Montgomery won an NCAA championship with the University of Maine in 1993 and played 122 NHL games as a forward for the Blues, Montreal Canadiens, Philadelphia Flyers, San Jose Sharks and Stars.
Montgomery was the eighth coach to be hired since the conclusion of the regular season. Lane Lambert was hired by the Islanders on May 16, Bruce Cassidy replaced Peter DeBoer as coach of the Golden Knights on June 17, John Tortorella was hired by the Flyers on June 17, DeBoer was hired by the Dallas Stars on June 21, Paul Maurice was hired by the Florida Panthers on June 22, Luke Richardson was hired by the Chicago Blackhawks on Monday, and Derek Lalonde was hired by the Detroit Red Wings on Wednesday.
With the Winnipeg Jets hiring Rick Bowness on Sunday, the Sharks are the only NHL team still searching for a coach.