The success of "The Ostrobothnians" was due to a confluence of factors: the appeal of the music, tonal but darkly colored; the use of folk melodies (blended with Madetoja's own idiom) familiar to the audience; a libretto (also by Madetoja) based upon a well-known and beloved play; a story about freedom from oppression and self-determination, the allegorical qualities of which were particularly salient in a country that had recently emerged from a war for independence; and, the skillful combination of comedic and tragic elements. The introduction to Act I (No. 2: "Prisoner's Song" in the suite), for example, is based upon a famous Ostrobothnian folk song, "Tuuli se taivutti koivun larvan" ("The Wind Bent the Birch"), which was one of the 262 folk songs Kuula had collected during his travels and which made its way into Madetoja's nationalistic opera, becoming its signature leitmotif.