The much-travelled Redknapp has managed six other clubs in England, including taking Tottenham into the Champions League and winning the FA Cup with Portsmouth.
Here Press Association Sport takes a look at how Birmingham came to appoint him as their manager and what the future could hold at St Andrew's.
How did it come to this?
When Birmingham unexpectedly sacked Gary Rowett in December they were seventh in the table and only outside the promotion play-off spots on goal difference
Following just two wins and seven draws in 24 games Zola quit on Monday after the defeat to Burton, a match which ended with Birmingham fans chanting "we want Zola out" and the club just three points above the relegation zone.
How did Birmingham's owners get it so wrong over Zola?
Trillion Trophy Asia Ltd bought the club in October 2016 following the disastrous regime of former owner Carson Yeung who is in prison in China after being convicted of money laundering charges
TTAL announced the appointment of Zola on the same day Rowett was sacked and backed the Italian with money for signings in the January transfer window and also with a public announcement that his job was safe on April 10, only for a subsequent 1-1 draw at already-relegated Rotherham and the defeat to fellow strugglers Burton to then be followed by his resignation.
Can Redknapp keep Birmingham up?
Redknapp has an impressive CV having managed Bournemouth, West Ham, P ortsmouth, Southampton, Tottenham and QPR and having steered Pompey to an FA Cup win in 2008
First on his agenda is the little matter of a derby game at fierce local rivals Aston Villa on Sunday lunchtime
Then comes a home game on April 29 against a Huddersfield side who might still be in contention for automatic promotion at that stage
Finally Redknapp's new side go to Bristol City who could also still be fighting relegation on the final day of the season
It is hard to see where Birmingham will pick up even a single point
What will happen next season at St Andrew's?
Redknapp has said he only has a contract for the remaining three games of this season and claims talks about extending his stay will only be held if he keeps them up
The remaining three games will show him which of the current squad have the stomach for a fight and, should he stay, he will look to TTAL to fund a summer spending spree to try to reverse the downward spiral the club's playing fortunes took under Zola
What does the future hold for Birmingham?
The owners certainly backed Zola who signed several players in January and Redknapp, or his successor, will have a rebuilding job on their hands
Birmingham players were involved in a public row after the Rotherham draw and the current squad will need freshening up in the summer
A spell in League One might be the best place to do that but TTAL will have to take a significant hit on the value of its investment in the meantime
Sheffield United have only just secured a return to the Championship after dropping into League One in 2011, showing how hard it is to get back.
Source : PA
Source: PA