The Norwegian government is in the process of introducing rules that will make the name “Norwegian aquavit” (norsk akevitt) a protected denomination, according to Kraftbyraa.no. The rules will e.g. require that the aquavit must be made in Norway (seems reasonable), must be made from potatoes (which apparently is not the usual raw material in other Nordic countries or in Germany), and must be aged for at least six months in barrel.
Norsk akevitt is, also according to Kraft Byrå, normally aged in sherry cask that is rarely used in other countries. This gives the Norwegian Aquavit a special character. (Aquavit is a typical Nordic distilled spirit. It is made from a white, neutral spirit to which spices and herbs are added to give it character.) Read more Kraftbyraa.no