Rooney left Everton for Old Trafford in 2004 and returns after winning five Premier League titles and a Champions League with Manchester United.
And the 31-year-old forward returns to Goodison Park 13 years later on a two-year contract.
He told Everton's official website: "It is some time since I said that the only Premier League club I would play for other than Manchester United was Everton, so I am delighted that the move has happened.
"Thirteen years ago I went to United with the intention of winning trophies and I have been fortunate to be a part of one of the most successful periods in the club's history.
"I have come back to Everton because I believe Ronald Koeman is building a team that can win something and I look forward to playing my part in making that a reality for the club I have supported since a boy."
United manager Jose Mourinho paid tribute to the England international and suggests he'll miss his experience and leadership in the dressing room.
Mourinho said: "It is no secret that I have long been an admirer of Wayne; he has been a model professional throughout his time at the club and will remain in the history books for many years to come.
"It is never easy to see a great player playing less football than he would like and I could not stand in his way when he asked to go back to Everton.
"His experience, focus and determination will be missed and I wish him well for the future."
Ronald Koeman was full of praise for his new signing, saying: “Wayne has shown me that ambition that we need and that winning mentality – he knows how to win titles and I’m really happy he’s decided to come home.
“He loves Everton and he was desperate to come back. He is still only 31 and I don’t have any doubts about his qualities. It’s fantastic he’s here.
“It’s all about his fitness and his desire, but he has shown me that ambition that we need. He knows how to win titles, as I said. No-one in the team except Gareth Barry and Davy Klaassen [in the Eredivisie] have won titles. The Under-20s are World Champions but not in the Premier League. He is that player. And don’t forget the experience he will give to the rest of the team.
“Wayne, of course, is still competitive – he will be a competitor always – and he wants to play at the highest level that is possible for him. We have spoken several times about Everton and what we are striving to achieve.
“That’s really interesting for Wayne and a lot of football players and, of course, in the situation of Wayne he was here at the beginning when he was young player for Everton. It’s his home and he likes that competition, he likes that pressure. I’m really happy that he finally decided to come back.
“His main quality is his quality on the ball, his experience and what I describe as his winning mentality. Everybody knows he can play out of different positions up front. He’s a smart player. He’s an experienced football player and that helps everybody.
“We have a lot of young players and sometimes in life you need somebody who you look up to, who you learn from. That was also one of the messages when we spoke about on and off the pitch what his function will be in the team.
“One of the functions for Wayne is to show the rest of the team why he is - and still is - that player.”
Source: Daily Express