Elias Lonnrot was a district doctor who spent years on foot and by boat in Karelia, sitting with singers and writing down runic song in the old trochaic metre. He published a first collection in 1835 and an enlarged one in 1849. The result gave Finland a national epic at the moment it needed one, and it gave the study of Finnic religion its principal body of material.
It is important to be exact about what the Kalevala is. It is not a transcript. Lonnrot selected, ordered, edited and in places wrote connective material, assembling a continuous narrative out of songs that circulated as separate items with no single sequence. The raw collections he and others made survive separately and run to far more material than the epic contains, which is why scholars work from the archive rather than from the poem when they want the tradition rather than the artefact.
What comes through the poem is still substantial: Vainamoinen the singer whose power is verbal rather than martial, Ilmarinen the smith, Louhi of Pohjola, and the sampo, an object that brings prosperity and whose nature is never settled. The sampo has been read as a mill, a pillar of the world, a sun symbol and a coin die, and no reading commands agreement.
The revival that draws on this material is small. Karhun kansa, meaning the people of the bear, was registered as a religious community in 2013 and takes the bear ceremonialism recorded in the songs as a central image. It does not claim unbroken descent. Neither do the researchers, who are generally clear that the Kalevala preserves a poetic tradition in which religious material is embedded, not a liturgy anyone can reopen.