Sami languages were repressed at least to the 70ies I think, with most success in the post-war period when societal service expanded and industrial jobs were plenty and well-payed. With beginning in the 80ies there was a shift in policy towards education in native languages and perhaps more importantly education in all sami-speaking schools (naturally with education in Swedish as well). Now even Ume-Sami with about 20 native speakers is a target of an effor to teach it so that it is not lost.

So roughly, there are old people who learned the languages before repression was effective, middle-aged who learnt a bit at home but were taught not to use it and used Swedish in the new environments they arrived in, and young who have learnt it from grand-parents and in the schools.

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