Thanks to a comment from a reader with a link, I found the following Local History Section of a Norwegian website with an article entitled, "Map heritage." The article by Marianne Herfindal Johannessen, refers to an online collection of 8000 historical maps of Norway from the Norwegian national mapping Authority. These websites are in Norwegian and if you do not read the language, you can use Google Translate to almost instantly translate the pages into pretty acceptable English.
The Historic Maps are on the a separate website called appropriately, Historic Maps. Here is a screenshot of the website: