> As an aside, I always thought from the name that he must be originally Dutch, but nope, he's a third-generation Swede; the name comes from his grandfather.

I assumed that too. It's surprisingly common to see long distance (5k and 10k) skaters with Dutch names competing for other countries. Quite often it's someone who emigrated or who is half-Dutch. Occasionally it's strategic: Bart Veldkamp moved to Belgium so he could more easily qualify for the longer distances without having to compete with massive numbers of Dutch skaters on the shorter distances.

I believe Nils' Dutch grandfather moved to Sweden and married a Hungarian woman there. Nils is all Swedish, though.