After bursting onto the scene at Everton, Rodwell moved to the current Premier League champions two years ago.
The 23-year-old endured a disappointing stint at the Etihad Stadium, however, as a raft of injuries coupled with City's wealth of options in midfield meant he made just 28 appearances in all competitions during his stay at the club.
On Tuesday, it was confirmed that Rodwell had agreed a switch to join Gus Poyet's side as Sunderland seek to improve on last season's finish of 14th.
"I met up with the head coach and all the people involved with the club. They told me about the club and their vision and it swayed me," Rodwell told Sunderland's official website.
"It's such a good club with passionate fans and I can’t wait to get on board. This is a great place for me to be."
Rodwell becomes Poyet's fifth signing of the close-season following the arrivals of Costel Pantilimon, Billy Jones, Jordi Gomez and Patrick van Aanholt.
Capped by England on three occasions, Rodwell will hope to recapture some of the form that saw him catch the eye at Goodison Park.
He made 109 appearances for Everton before securing a move away but will face competition for a place at the Stadium of Light from the likes of Lee Cattermole, Sebastian Larsson and former Swansea City man Gomez.
Rodwell could make his Sunderland debut against Real Betis on Thursday or Udinese on Saturday before the club's Premier League opener against West Brom on August 16.
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