Specifically, I'm talking about examples where it's implied characters learned languages as second languages, not from being natively multi-lingual.
Related: did people actually learn languages? I know that in some places with a wide variety of regional languages, you just hear it spoken around you until you eventually start to understand it. In the days before widespread formal education, would my only option to learn a language be to move to an area where that language is spoken and hope for the best?