Tomasson, 45, joins Rovers having won two consecutive league titles with Swedish club Malmo FF.

Blackburn finished eighth in the second tier table last season, six points outside the play-off places.

Chief executive Steve Waggott told the club website:

"It has been a long process, but we are really pleased to have eventually secured the services of such a young and ambitious coach in Jon."

"I'm really proud and excited to be taking over as head coach of Blackburn Rovers - a club with a lot of tradition and also great ambition," Tomasson, who won the Champions League during his time with AC Milan, said.

"We have a young team here, and also a great academy, and the owners have a clear vision, which is to develop players and become a sustainable Premier League club over time, so I'm really happy to be involved in this exciting new chapter for the club."

Rovers appointed Gregg Broughton as their new director of football last week.

Broughton has taken responsibility for football strategy at the club, including the first team and academy as well as recruitment.

Despite a promising start to 2021-22 that had seen them as high as third, Blackburn faltered badly in the second half of the campaign and missed out on a top-six spot.

The club have now spent 10 years outside English football's top flight, the past four in the Championship after Mowbray led them back to the second tier at the first attempt following their relegation to League One in 2017.

Analysis - 'Tomasson taking on big job'

BBC Radio Lancashire sports editor Andy Bayes

The appointment of Jon Dahl Tomasson at Blackburn Rovers was looking likely over the last five days or so.

They were linked with Daniel Farke, Carlos Carvalhal, Gareth Ainsworth, Michael Beale and Duncan Ferguson over recent weeks, but it is Tomasson, who was out of the game after a two-year spell with Malmo, who has been given the opportunity of replacing Tony Mowbray at Ewood Park.

The Dane is new to the Championship, and it's 25 years since he last arrived on English shores as a Kenny Dalglish signing for Newcastle United. His spell with the Magpies lasted for a season before more successful spells with Feyenoord, AC Milan, Stuttgart and Villareal.

As a coach, he's had a successful period with the Danish national team, helping them reach Euro 2020 as assistant coach, before securing back-to-back league titles for Malmo in Sweden, and perhaps more impressively, negotiating four qualifying Champions League qualifying rounds to reach the group stages.

Blackburn Rovers is a big job. The club haven't reached the play-offs in 10 years since relegation from the Premier League and it remains to be seen what level of financial backing will come from the club's owners in India.

Recruitment will be the key with out of contract departures and last season's loanees returning to their parent clubs. Some big weeks await new director of football Gregg Broughton and the newly appointed head coach.