Should you have a Norwegian spouse, you can apply for citizenship after you have lived in Norway for five years and have been married or have lived with a Norwegian for a total of seven years. As the rules for claiming citizenship when one parent was Norwegian at birth can be quite complicated for those born before 1979, the Norwegian Directorate of Immigration (UDI) advises that you contact them directly to find out whether you will be eligible for citizenship. Meanwhile, those born before September 1st, 2006 can become Norwegian through parentage if their mother was Norwegian, or if their father was a Norwegian citizen and was married to their mother.