Amir, Sorry that Wikipedia not is up to date:
“At an excavation in the area around Vivungi, Sweden, archaeologists have made sensational findings. They have discovered slag from ovens that shows that iron production has taken place 2000 years ago in Norrbotten inland - completely new information, which means that the history of Norrbotten has to be rewritten. Findings of this type of furnace have been found in Finland, Karelia, but also in Bergslagen.
Residues from fish bones and other burned food waste residues from the site around the iron ovens show that there was iron production in a hunting and catching environment at this site during the early Iron Age.
-I think that a lot of our iron technology comes from the eastern side of the Baltic sea, but who these people were we do not know.”
https://www.svt.se/nyheter/lokalt/norrbotten/arkeologiska-fynd-skri...
https://www.svt.se/nyheter/lokalt/norrbotten/foradlades-jarn-i-lane...
2000 years ago it was Finnish Speaking people on the eastern side of the Baltic Sea.
Probably in Sweden as well.
The Finno-Ugric peoples are any of several peoples of North-West Eurasia who speak languages of the Finno-Ugric group of the Uralic language family, such as the Khanty, Mansi, Hungarians, Maris, Mordvins, Sámi, Estonians, Karelians, Finns, Udmurts and Komis.
https://en.wikipedia.org/wiki/Finno-Ugric_peoples