Gregory Maxwell wrote:
Although it's quite possible, and even likely, that some are misreported the claim that users from NL and BE are highly multilingual is supported by data across more than a dozen wikis.
Absolutely, all the honor to the Dutch and Belgians! But this cannot be taken to the level that they make up 26.7% of contributions to the Danish Wikipedia. The Danish Wikipedia was the most striking example, so I suggest you take a look at which IP address ranges (group by size /20 network) that contributed to the Danish Wikipedia were reported as coming from the Netherlands. It should be fairly easy to identify one or two big ISPs there. Then ask on the Danish village pump how this can be explained. Some local users are sure to know how their own IP addresses work. No need for separate tools, even though that could be nice too.
What was the name of the geolocation database you used?