Birmingham hired Tony Mowbray as their new manager on Monday to replace the sacked Wayne Rooney.
Former Sunderland and West Brom boss Mowbray agreed to a two-and-a-half-year deal with the Championship strugglers.
He is Birmingham's third manager this season after the dismissals of John Eustace and Rooney.
"I am excited to be joining Birmingham at this time. I can't wait to get back on the training pitch and start working with this talented group of players," Mowbray said.
"I know from personal experience how passionate Bluenoses are, home and away, and I'm looking forward to having their full support for the team starting Saturday at home to Swansea."
Mowbray was sacked by Sunderland in December after 15 months in charge, despite guiding them to the play-offs last season.
Former Manchester United and England star Rooney was axed by Birmingham after just 83 days in charge, having replaced Eustace in October.
Rooney managed just two wins in 15 games as Birmingham slipped from sixth in the Championship to 20th.