Seppo Ilmarinen, the Eternal Hammerer, blacksmith and inventor in the Kalevala, is an archetypal artificer from Finnish mythology. ("Seppo" is a popular boy's name and the Finnish word for smith "seppä" is derived from it, or vice versa.) Immortal, he is capable of creating practically anything, but is portrayed as unlucky in love. He is described as working the known metals of the time, including brass, copper, iron, gold and silver. The great works of Ilmarinen include the crafting of the dome of the sky and the forging of the Sampo.
Other names for Ilmarinen that are found in rune variants include Ilmorinen and Ilmollini. The name Ilmarinen is also close to that of the Udmurt deity Inmar. Originally a sky god credited with creating the sky (ilma means air in Finnish), he is believed to have taken on the qualities of a smith through the Proto-Finnic contact with the Indo-European Balts. He is also directly appealed to for aid in several incantation runes. Insofar as Elias Lönnrot heavily redacted the original runes collected by him and others, it's valuable to differentiate between the Kalevala and the original poems sung by rune singers.