How do you see a Sweden supported German front opposed by a Norwegian, British and French playing out? I first thought of the Austrian-Italian Front.Â
Such an action by Germany would have led to many Jutland style fleet battles.
It only was one Jutland battle, and the lesson from it was don’t do it again, as Marc just explained.
As for the maritime strategy, the French coast is far more valuable than the Norwegian coast, both for excess to own shipping and trade, and for denial of the enemies. During WWII, Germany did in fact, yes I am not kidding, they did occupy both the Norwegian coast and the French coast, and the French coast proved far better, since it had short range to the action. If you own a Globe, you will see that Norwegian ports are easy blocked by the Greenland\Iceland\UK gap. KM Bismarck would learn this the hard way. Owning Norway is only a benefit if you want to go skiing to the North Pole.
Now, for the Norwegian Sweden Front. This did not happen neither during WWI nor WWII, because no one would benefit from it. But for the sake of discussion, lets assume it happened. A WWI attack on Norway would be different from the historical one in april 1940, because in in 1914 Norway was kind of allied to Britain, in a nonbelligerent treaty, plus Norway was totally mobilized from day 1. A German 1914 attack would have to go through Sweden, unless they wanted to see their navy sunk. So now we talk about a mountain war in the arctic zone, btw have you ever been to Alaska ? In 1914 there were no mentionable roads nor railroads in Norway, so they would get a hard time to supply this front. Both the terrain and the climate would favor the defender, making the front look like the winter war in Finland or the Litza front. Because of the 1905 tension between Norway and Sweden, the border had plenty of fortified lines too, in addition to the mountains, lack of roads, snow in the winter and marshes in the summer. In fact, Fort Hegra was tested in 1940 when a German battalion used 4 weeks of siege to crush the 200 Norwegian defenders. A full scale attack would be a mess. The Russians attacked 10 to 1 at the Mannerheim Line, and kept on for 4 years before they realized it was a bad idea. German crack mountain divisions attacked 5 to 1 against the Murmansk division, bet never got behind the Litza river. The Allies attacked Narvik in 1940 with 35000 men against 5000 German gebirgsjeagers, and after 2 months the Germans won. Attacking mountain fortresses in winter is always a bad idea. Same goes for an Allied attack against the Swedish iron mines at Kiruna. I spent some of my military service up there in the 80ties, and cant belive how Churchill in 1940 would think it was even remotely possible to walk 50 000 Brits over the mountain with no skies and no supply and no winter gear.