Svenska dagen på svenska. Ruotsalaisuuden päivä på finska.

"Finnish Swedish Heritage Day (Swedish: Svenska dagen, Finnish: ruotsalaisuuden päivä) is a general flag flying day, which is celebrated in Finland on 6 November. The day celebrates the Swedish-speaking population of Finland, their culture, and the bilinguality of Finland.[1] The main celebrations are aired on the radio, and many smaller celebrations are held around Finland in schools. Usually, the song Modersmålets sång is sung, celebrating the mother tongue. The Finnish Swedish Heritage Day is celebrated on the same day as Gustavus Adolphus Day in Sweden, the day that king Gustavus Adolphus of Sweden was killed at the Battle of Lützen in 1632.[2][3]"

Learn more:

https://en.wikipedia.org/wiki/Finnish_Swedish_Heritage_Day?fbclid=IwAR08T93Duk1ZYgUi6Iiqvu-bSmIzKgXYjYLfmWg4LfsjVx2j0L9CeWzeO4k