Redknapp, who was manager of Tottenham when the decision was made, said he wanted Liverpool boss Brendan Rodgers - then with Swansea City - to be his assistant.
"My thinking on Brendan was this: if he can do it with players from the lower leagues at Swansea what can he do with Rio and Terry or Rooney and Gerrard?" he added.
"So when Tottenham played Swansea on 1 April, 2012 I pulled Brendan after the game and said that if all the speculation about me and England was true would he consider coming to the European Championships in the summer as my part-time coach?
"I told him I wanted England to play with as much technical ambition as Swansea. He was up for it.