The company had advertised the position following the exit of Esure's top marketer, Mary Davidson, earlier this year to a role within parent company HBOS. But after relinquishing a number of external commitments, Wood has decided to return to the front line.
Wood said that he wanted to 'inject marketing vision at this crucial stage of our brand development'.
He added: 'Rather than attempt to find a senior marketer who understands the insurance market, I have decided to make the best use of my own understanding of it.'
Wood has also hired Chris Wilkins and Sian Vickers to work with him as brand consultants at group level. The duo helped him establish Direct Line in the early-90s.
The current heads of marketing for Esure and First Alternative - Chris Bowden and Andy Brown respectively - will report to Wood.
Esure, which was created three years ago, is the UK's fastest-growing insurance company ever, and has so far acquired 850,000 customers. Sister brand First Alternative, which targets high-premium drivers, started trading earlier this year.
Esure's ads are created in-house and famously feature restaurant critic and film director Michael Winner.