Marsh, who will leave at the end of the season, is joining the Football Association to work primarily with the England Under 17 team.
The appointment of the former Liverpool player and coach is part of a large-scale restructuring at the FA with permanent technical and medical staff based full-time at St George’s Park in Burton-upon-Trent under technical director Dan Ashworth and head of team strategy and performance Dave Reddin.
Other appointments alongside Marsh, who will work with England Under 17 head coach Steve Cooper, include former Everton, Birmingham City and Republic of Ireland midfielder and Brentford manager Lee Carsley, ex-Middlesbrough, Nottingham Forest and England defender Colin Cooper, a former Hartlepool United boss, and Mark Robson,the former West Ham United and Charlton Athletic midfielder who was an assistant of Tim Sherwood at Aston Villa.
The FA’s head of development team coaching Matt Crocker explained: “These coaching roles have been designed to help us maximise the time on the pitch we have with the players for the international stage.
“It will really enable us to have a greater focus on particular areas of preparation and ensure we are developing the style of play we want to see from our development teams, as part of the England DNA.
“Bringing in the calibre of the coaches that we have can only help us to produce winning England teams in the future.”
Both the England Under 17 and Under 19 teams have reached their respective European Championships and the Under 21s are unbeaten in their qualifiers.
Marsh, 46, who also played for West Ham, Coventry City, Galatasaray, Southend United and a string of non-league clubs, and coached within Liverpool’s academy system before stepping up to first-team level at Anfield under Brendan Rodgers, arrived at Town alongside Wagner in November.
Hoyle wanted a coach with experience of the English game to help Wagner and Buehler make the transition from German football.
“Mike has done a good short-term job for us,” said Hoyle.
“We knew a while ago that he might be joining the FA, and it’s an attractive job.
“We will move on, and we have his replacement lined up.”