The Kalevala exists because a country doctor named Elias Lonnrot spent much of the 1830s traveling on foot and by boat through remote Karelian villages, notating oral poetry still sung there by traditional singers, material scholars believe preserved genuinely pre-Christian Finno-Ugric mythology that had otherwise almost entirely vanished from more Christianized and urbanized parts of Finland. Rather than publishing the songs as a loose folklore collection, Lonnrot selected, arranged, lightly connected and in places supplemented thousands of individual verses into a single continuous epic narrative, opening with a creation account in which the sky-maiden Ilmatar floats on the primordial sea until a bird nests on her knee and its broken eggs become the earth, sun, moon and stars, and her son Vainamoinen, an ancient shaman-poet, is born already old and wise.
The epic's central plot concerns the Sampo, a magical mill or artifact forged by the smith Ilmarinen that grinds out grain, salt and gold, fought over between the heroes of Kalevala and the sorceress Louhi's northern realm of Pohjola, alongside the tragic story of Kullervo, a boy raised in slavery who unknowingly commits terrible wrongs against his own family. The epic closes on a startlingly syncretic note, Vainamoinen departing as a virgin named Marjatta gives birth to a child recognized as a new ruler, an ending scholars read as Lonnrot's own bridge between the old pagan material and the Christian Finland he lived in.