The Rams have ended Liam Rosenior’s brief reign as interim boss and confirmed Warne as Wayne Rooney’s everlasting successor.
Warne oversaw six profitable years at Rotherham – who currently sit eighth within the Championship after a vivid begin to the campaign.
Derby, in the meantime, are seventh in League One as they bid to struggle their approach again into the second tier.
Warne is a man with experience when it comes to profitable promotion from League One, having guided the Millers again to the Championship thrice in six years, boasting a 100 per cent success price.
Derby said in a statement: “As was made clear in the summertime, the board supposed to take a interval of time evaluating each side of the membership and having carried out that, we consider Paul’s observe record of success at this stage matches completely into our long-term technique.
“He has gained promotion thrice from League One in virtually 300 matches as a manager, as nicely as the Papa Johns Trophy last season, and his latest achievements with Rotherham United spotlight his potential and experience, two components which will be important on this pivotal season for Derby County.
“Paul’s arrival means the tip of Liam Rosenior’s tenure as interim manager and, on behalf of everybody at Pride Park Stadium, we wish to thank Liam for all his efforts throughout an extremely tough interval and in serving to to stabilise the membership under new possession.