I got curious about the nature of these edits, so I picked out a half dozen at random to try and make sense of the articles in question and what was changed
(I don’t speak Norwegian, so this is slight guesswork, relying on context and my study of language and general linguistic skills, and a bit of google-fu and brute translation where necessary).
- Danmarks ambassade i Oslo
I got this right away: Denmarks’ Ambassador / Embassy in Oslo. The edit appears to have been updating and fixing a link to a .pdf file titled “The Oslo Diplomatic List”.
- Mogens Thorsens gate
Another relatively simple one, “Mogens Thorsens gate” is a street in the city of Oslo, named for Mogens Thorsen, and the edit was the correction of a typo, with “Thorsen” having previously been “Thorson”.
- Kristen Tobias Rivertz
This article had formatting which supplied ample context, allowing me to easily determine that Kristen Tobias Rivertz was a Norwegian architect, who lived from 1862 to 1937, and who apparantly has connections to the city of Oslo.
The edit in question was a simple formatting update, changing “Frogner terrasse” to “Frogner terrasse (Oslo)” - presumably this -terrace- was one of Rivertz’ works, and presumably there is another terrace elsewhere with the same name, hence the specification of (Oslo).
- Henry Bucher
Another Norwegian architect, 1864 to 1944, again associated with Oslo. This edit merely added a few pictures to the gallery, specifically of Huitfeldts gate and Akersgata, apparently two more streets akin to Mogen Thorsens gate.
- Byantikvarens gule liste
Apparently this is a “kommune” in Oslo, which seems to essentially refer to a small region or district. The edit was the removal of an external link, apparently to a document hosted on the commune’s official website, presumably because the link led to a document that was moved or no longer existed.
- Sørumsand stasjon
A railstation located in Sørum, built in 1892. The edit resized two image thumbnails to be slightly smaller.
I know that’s a small sample size, but we’ve got a clear trend that tells us a decent amount of information about the nature of these edits. The articles edited seem to be chiefly concerned with notable locations and architecture, specifically focusing on the late 19th and early 20th centuries. The edits themselves are very small, very subtle, and entirely utilitarian.
As unexciting as it sounds, this small sampling suggests most of these edits appear to have been completely innocuous, with no political or ideological motivation whatsoever. Better luck next time, eh Boundegar? 
At the same time, Mr. Doctorow’s hopeful commentary about…
“how great it would be if all these Norwegian bureaucrats, wonks, officials and others declared their interest and made their efforts public, working with Norwegian wikipedians to improve the quality of the encyclopedia in the open”
…ends up being just a little over-optimistic, as the nature of these edits is so minimal and jejune as to hardly be worthy of consideration for any sort of official recognition whatsoever.
It seems likely to me that these edits are simply the work of individuals within the government who have personal interests in contributing to wikipedia in small ways in their free time while on breaks or whatnot. Perhaps some of them are regular non-anonymous contributors in their private lives, but when making contributions from government systems, they err on the side of caution and discretion and post anonymously?
Sadly, I can’t with any veracity explain the recent increase in contributions from government IP addresses.
If I had to speculate, I would hazard a guess at it being a topic of discussion among various circles of government employees - perhaps those with shared interests, such as history, landmarks, architecture, and the like? Or might it even be that these edits are the works of employees of a government library or archive involved in such fields?
