The 6'0" defender was a Middlesbrough trainee, and was an active member of their first team squad until last year. He also gained international experience while at Boro, playing for England at Under-21 level during Taylor's first reign as coach of them, as well as going on to get five caps for the Scottish national side.
He went on loan to West Ham and Rotherham last season, and his stay at Millmoor turned into a permanent transfer in the summer. He played a further 29 first team games for them this season, but has been allowed to leave to free up funds for the Millers, who today announced that manager Ronnie Moore has left the club by mutual consent.
Stockdale will be the latest addition to the list of right-backs used since Taylor became City manager, which includes Carl Regan, Jon Otsemobor, Alton Thelwell, Richard Hinds, Lee Marshall, Scott Wiseman, Ryan France, Stev Angus and Marc Joseph.
The signing has resulted in City terminating Angus's loan deal with the club. He returns to Cambridge, but is tipped to sign for Scunthorpe.
It also means an uncertain future for Thelwell, Hinds and Wiseman, while Joseph will be looking to return to central defence when he recovers from injury.