The former Liverpool midfielder joined City on a free transfer from Bolton, and has signed a two-year contract with the Blues.
Hamann brings a wealth of experience to bolster Stuart Pearce’s midfield, and his arrival follows the capture of fellow midfielder Ousmane Dabo from Lazio.
After transferring from Bayern Munich to Newcastle United in 1998, Hamann spent one season in the north-east, where he was a team-mate of Pearce’s, before moving to Liverpool.
In his seven years there, Hamann played a major part in the club capturing a string of honours, and scored from the penalty spot in both last year’s Champions League and this year’s FA Cup final shoot-outs.
Capped 57 times by his country, ‘Didi’ also holds the distinction of being the last player to score at the old Wembley, his free-kick being the only goal of the game when Germany played England in October 2000.
Hamann will wear the number 21 shirt.
