Ian Burchnall, 38, takes over at Meadow Lane after Neal Ardley left the Magpies on Wednesday.
Burchnall, according to Notts, ‘is regarded as one of football’s most exciting young coaches’.
He has eight years of experience in Scandinavia, first as Brian Deane’s assistant at Norwegian side Sarpsborg in 2012, before taking over at Viking FK in 2017.
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His next move was to replace Graham Potter who left for Brighton, at Swedish side Ostersund FK.
Burchnall led Ostersund to a sixth-place finish, one point and a place below the record set by Potter the previous year, before leaving last summer.
County are currently sixth in the National League, four places and four points above the Spireites.
“As part of our ongoing extensive research, we compile detailed profiles of many different coaches and Ian stands out as an outstanding prospect,” County owners Chris and Alex Reedtz said.
“Despite his young age, he has tremendous experience of working in top-flight football and has been linked with several international and club roles since his departure from Ostersund. We feel very lucky to have him and have every confidence that he is the right man to complement our model.
“It’s our hope that Ian will be able to continue our push for promotion this season but we understand it will take him time to fully implement our philosophy. He is a long-term appointment for this club and his performance in the role will be judged on that basis.”