"I'm extremely proud and privileged to get the opportunity to lead this group of players," Root told Sky Sports News. "It was a no-brainer that I was always going to say yes to the job and I am now just really looking forward to all the challenges that lie ahead.
"I like to think I'll be quite instinctive as a leader. I want our team to be tough, and always be looking to win. I want us to be an enjoyable side to watch. You see the way that the one-day side has lifted over the last year or so - the way the guys have gone about playing their cricket - that's something I want to bring to the Test arena as well.
"We've done some very special things as a Test team over the last five years or so, and Cooky has been a fantastic leader, but I think with the group of players we've got now, it's a great opportunity to take the team to the next level.
"Cooky sent me a lovely message when he found out I was going to take on the role. I'm really looking forward to working with him - he's still going to play a massive part of our team moving forward."
Root's first match at the helm will come against South Africa at Lord's on July 6.