Short answers, pulled from the story.
Bergslagen is a historical, cultural, and linguistic region located north of Lake Mälaren in northern Svealand, Sweden. It is traditionally known as a mining district, generally covering parts of the provinces of Västmanland, Dalarna (the southern part), and Värmland (the eastern part).
The earliest signs of iron making in Bergslagen date back to 400 BC. Industrial-scale mining and metallurgic activity in the region began in the 17th century.
The conflict between iron exports from Bergslagen and Denmark's territorial ambitions at its southern border was a chief reason behind the Engelbrekt rebellion of 1434. The strife that followed ultimately led to the dissolution of the Kalmar Union in 1523.
A total of 270 mineral species have been reported at Långban, where iron and manganese have been mined. Sixty-seven of those minerals were first discovered at the Långban deposit.
Bergslagen functioned as an industrial powerhouse from the 17th century until the Steel crisis of the 1970s. Most mines in the region are now closed, though many were still in operation during the 1970s.
Typical towns in Bergslagen include Lindesberg, Nora, Fagersta, Sala, Kristinehamn, Filipstad, Grythyttan, Ludvika, and Hedemora. Broader definitions of the region can also include Hofors in Gästrikland and Finspång in northern Östergötland.