Sweden Under-21s manager Poya Asbaghi has been confirmed as his replacement and will work alongside assistant Ferran Sibila.
Caretaker manager Joseph Laumann will remain in charge for Saturday's trip to Fulham, with Asbaghi officially beginning his duties on Monday.
He was in Dublin on Tuesday night as Sweden Under-21s conceded a stoppage-time winner against the Republic of Ireland in an Under-21s Euro 2023 qualifier.
Here is the lowdown on the new Tykes boss as he has the task of saving the club from dropping into League One.
He has been on Barnsley's radar before
Asbaghi was interviewed for the Oakwell job two years ago following Daniel Stendel's departure.
The Barnsley hierarchy eventually opted to appoint Austrian Gerhard Struber as he guided the Tykes to safety with a dramatic late escape at the end of the 2019-20 season.
Asbaghi was viewed as not having enough experience the last time the Reds were interested in his services but he has remained coaching since 2019.
He has a major trophy to his name
In 2020, Asbaghi guided IFK Göteborg to Swedish Cup glory.
After winning both their quarter-final and semi-final in extra time, against Hammarby IF and IF Elfsborg respectively, Göteborg set up a final with Malmö FF.
Malmö would go on to win the Allsvenskan - Sweden's top league - last year but were beaten in the Cup final by Asbaghi's side who won 2-1 after extra time.
A decent amount of coaching experience
Between 2014 and 2015 he was assistant coach at Dalkurd FF, who currently play in the Swedish third tier. He become manager in 2016 before leaving in 2017. In the same year, he spent time in charge at Gefle IF.
In 2018, Asbaghi was named manager of IFK Göteborg. After guiding the club to an 11th-place finish in the 16-team division in 2018 and a seventh-placed finish the following year, his contract at the club was extended to 2022.
In 2019, he was nominated manager of the year in Allsvenskan before being approached by Barnsley in the autumn prior to Struber's appointment.
In November last year he was appointed manager of Sweden Under-21s until the summer of 2023.
He has European experience
In 2019, he earned Göteborg a spot in the second qualifying round of the Europa League. It was the first time in three years that the Swedish club had reached some form of European competition.
However, they never advanced further in the Europa League under Asbaghi as they were beaten 2-1 by Copenhagen in the qualifying round.
Grew up in Sweden after his family fled Iran
The 36-year-old was born in Iran but his family fled to Sweden when he was younger because of political persecution.
He grew up in Sweden's fourth-largest city, Uppsala, which is located approximately one hour north of the Swedish capital Stockholm.