Norway-Sweden border

The Norway–Sweden border (Norwegian: Svenskegrensa, Swedish: Norska gränsen) is a 1,630-kilometre (1,010 mi) long land national border, and the longest border for both Norway and Sweden.

The border was changed several times because of war. Before 1645, Jämtland, Härjedalen, Idre/Särna parish, and Bohuslän belonged to Norway. The border changes were defined in the Treaty of Brömsebro (1645), the Treaty of Roskilde (1658) and the Treaty of Copenhagen (1660).

In 1751 a treaty was signed in Strömstad, defining the border based on field investigations and negotiations done 1738-1751. The border was based on knowledge among local people, mainly which farm belonged to which parish and which parish to which diocese. In the unpopulated mountains, the border mainly followed the water divide. There were disagreements on the parishes of Särna, Idre, Lierne, Kautokeino and Karasjok, which had to be solved by give-and-take. Based on that, in 1752-1765 border cairns were erected between Norway and Sweden including Finland, which mostly remain today.

After the Treaty of Kiel and the Convention of Moss (1814) the union between Sweden and Norway was established, and the Norway–Sweden border became a border between two union partners. In the Negotiations in Karlstad which led up to the dissolution of the union in 1905, Norway was obliged to tear down several fortresses along the border.

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Wikipedia