Lyrically, the band deals with topics on fantasy, mythology, nature, the cosmos, and metaphysics.
Solens rötter, marked a return to the earlier folk metal style, while retaining the more complex and non-traditional guitar arrangements and song structures of later albums.
On earlier albums, the lyrics are all written and performed in Swedish, and dealt with topics of nature and paganism.
In the Cosmic Genesis booklet, Vintersorg extends thanks to Dr. Carl Sagan, author of the book Cosmos.
In keeping with the band's return to its folk roots, the latter albums are also sung entirely in Swedish and deal with more traditional themes.