The midfielder's last call up came in November 2015, but Gareth Southgate has selected him for the first time in his time as boss ahead of clashes with Slovenia, on Thursday October 5 at Wembley Stadium, and Lithuania, three days later in the capital of Vilnius.
Delph has not started a Premier League game for City since April but could start as a makeshift left-back against Chelsea this Saturday.
The 27-year-old - one of two new faces from the last England squad alongside Fraser Forster - scored a stunning effort in City's 5-0 thrashing of ex-England boss Roy Hodgson's Crystal Palace last weekend, yet his recall still comes as a surprise due to his lack of consistent minutes.
Southgate has also named Tottenham Hotspur midfielder Dele Alli in his 26-man contingent despite the looming threat of suspension.
The 21-year-old could be suspended for as many as four competitive fixtures for an offensive gesture jokingly used towards team-mate Kyle Walker in a 2-1 win over Slovakia earlier this month.
Southgate hopeful over Alli hearing
FIFA's disciplinary committee are said to have come to a decision on the case on Thursday, though the result of that hearing is not expected to be made public until the next few days.
Upon naming his squad, by which time the Football Association had hoped to learn about Alli's availability, Southgate said: "We run the risk of looking a shambles because he could get withdrawn again. Our hope is that common sense prevails and he'll be available for our matches. We'll have to wait and see."
Alli could miss the first two group stage games of England's World Cup campaign next year if he is handed a maximum four-game suspension, but Southgate refused to confirm or deny whether he and the FA would appeal such a decision.
He said: "We have to look at what comes out of the hearing and go from there really. We've given our side of events, Dele's given his side of events. We have to see what happens next."
The England boss confirmed that he's had "a good chat" with Alli "about lots of different things" and insisted the "biggest disappointment" for the Spurs prodigy is "to miss football."
"The upshot of this is that he recognises the responsibility. He recognises it is important for him and for us that he's available for games," the 47-year-old continued, insisting it is "something he won't do again."
On Delph's return to the squad, Southgate explained: "Fabian was a very important player for Roy [Hodgson] at one point. He has suffered with injuries but has now forced his way into a very good side and played well. We are in a situation in midfield where we need more competition for places, more alternatives, and he can provide that."
Two new faces from last Three Lions' squad
The Three Lions are all but qualified for next summer's tournament in Russia already, sitting five points clear of second-placed Slovakia in Group F and needing only a win to secure their qualification. Even a draw would guarantee a top-two finish.
Still unbeaten, Southgate's charges have also conceded just three goals in eight games, two of those coming in a 2-2 draw away at Scotland back in June.
Yet even considering their comfortable advantage, Delph's inclusion in the squad is a shock.
But it is one necessitated by Southgate's lack of alternatives with injuries having limited his options in central midfield. It also shows Southgate's willingness to assess his options as he begins to draw up blueprints for his provisional 30-man World Cup squad, narrowed down to 23 players for the eventual competition.
Likewise, Southampton shot-stopper Forster replaces Tom Heaton with England picking four goalkeepers in Forster, Joe Hart, Jack Butland and Jordan Pickford - with only three of those to be included in their eventual team to travel to Russia next June.
Of those injured Leicester City striker Jamie Vardy drops out of the squad after missing the Foxes' last two games with a hip problem, while Watford midfielder Nathaniel Chalobah, Arsenal striker Danny Welbeck and Burnley goalkeeper Heaton all miss out through injury after featuring in the previous squad.
Others ruled out of contention include Liverpool's Adam Lallana and Ross Barkley of Everton, while Chelsea midfielder Danny Drinkwater and Spurs left-back Danny Rose are also sidelined.
Despite a foot issue having kept Michael Keane out of action for Everton's last three matches, the defender is expected to be involved for his country after being called up.
Manchester City, Manchester United and Tottenham - three of the Premier League's current top-four - all have four representatives in the squad, while third-placed Chelsea have just the one.
Full 26-man England squad
Goalkeepers: Joe Hart (West Ham United - on loan), Fraser Forster (Southampton), Jack Butland (Stoke City), Jordan Pickford (Everton)
Defenders: Ryan Bertrand (Southampton), Aaron Cresswell (West Ham), Gary Cahill (Chelsea), Phil Jones (Manchester United), Harry Maguire (Leicester City), Chris Smalling (Man United), John Stones (Manchester City), Michael Keane (Everton), Kyle Walker (Man City), Kieran Trippier (Tottenham Hotspur).
Midfielders: Jordan Henderson (Liverpool), Eric Dier (Tottenham), Fabian Delph (Man City), Jake Livermore (West Bromwich Albion), Alex Oxlade-Chamberlain (Liverpool), Raheem Sterling (Man City), Jesse Lingard (Man United), Dele Alli (Tottenham).
Forwards: Marcus Rashford (Man United), Harry Kane (Tottenham), Jermain Defoe (Bournemouth), Daniel Sturridge (Liverpool).