Bosz, 53, joins on a two-year contract after having led Ajax to the Europa League final, with Dortmund reportedly having agreed to pay the Eredivisie side €5 million.

Dortmund were said to have made Nice coach Lucien Favre their top target for the position but the French club issued a statement ruling out his departure and Bosz, who joined Ajax last summer after a short spell with Maccabi Tel Aviv, was then installed as the favourite.

Despite a slow start at Ajax in which they lost a Champions League playoff to Rostov, the former Heracles and Vitesse Arnhem boss ultimately led his young side to the Europa League final, where they were beaten 2-0 by Manchester United, while finishing runners-up to Feyenoord in the Eredivisie.

Bosz's side adopted an attacking approach inspired by his role model, the Ajax and Netherlands great Johan Cruyff, but reports in the Dutch media on Tuesday morning said he decided to leave the Amsterdam Arena in part down to a conflict over training and playing philosophy with other members of the coaching staff, including Dennis Bergkamp, who had been one of his assistants.

Bosz -- a fluent German speaker -- will be the second Dutchman to take charge at Dortmund as he follows in the footsteps of Bert van Marwijk, who coached the club as they battled bankruptcy in the mid-2000s.

He inherits a young BVB side that finished third in the Bundesliga last season, securing automatic Champions League qualification, and won the DFB Pokal, their first trophy in five years.

Chief executive Hans-Joachim Watzke said: "We held a lot of talks in recent days. Once we started talking to Peter Bosz we had a very positive feeling from the outset. Besides the sporting ambition, it was also deciding that we had the feeling that something could grow here [with Bosz]. We also want to thank Ajax for their cooperation to let [Bosz] seize that opportunity."

Sporting director Michael Zorc added: "First and foremost, we're convinced with Peter's coaching philosophy which is similar to the style we and our fans want to see. Peter's coaching philosophy is a very attacking minded one. A structured possession football coupled with gegenpressing. It's a good balance. We also like that Peter Bosz is not reluctant to play young players in big games."

Bosz said: "BVB [are] maybe one of the 10 biggest clubs. I'm looking forward to the legendary yellow wall. The first talk with Watzke and Zorc, which lasted three hours, convinced me that BVB is the right next step for me."

Tuchel, who had replaced Jurgen Klopp in 2015, left the Westfalenstadion after a tumultuous season in which there were regular reports of disagreements with both the club hierarchy and senior players.