Pagano, who coached the Colts for six seasons, will take over for former defensive coordinator Vic Fangio, who accepted a new job as head coach of the Denver Broncos earlier this week.
“We are excited to add Chuck to our staff as defensive coordinator,” Bears G.M. Ryan Pace said. “He has successful experience at many different levels in this league and he is a great teacher with an aggressive mentality that fits our style of football. He is a man of high character and has a passion for the game that will no doubt add to the culture we have already started building at Halas Hall.”
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Pagano led the Colts to a 53-43 record during his tenure, but was fired at the end of the 2017 season.
He will be taking over a Bears defense that was one of the league's best, largely thanks to the efforts of Fangio.
Pagano has served as an NFL coach for several teams, including as a position coach and a defensive coordinator for the Baltimore Ravens before accepting a job as Colts head coach.
The coach became a national inspiration after battling leukemia during the 2012 season. After a leave of absence, he returned to the team for the final game of the regular season, and then coached the team in the NFL playoffs.