WIKIPEDIA:

“ Metsatöll is an Estonian folk metal band.The name "Metsatöll" is an ancient Estonian euphemism for wolf, which is reflected in the harshness of their lyrics. Much of their material, featuring flutes and other traditional instruments, is based on the wars for independence of the 13th and 14th centuries.

History
Metsatöll started playing together on 24 February 1999 as a three-piece (Markus – vocals and guitar, Factor – drums, Andrus – bass), playing epic heavy metal with small influences from ancient Estonian folklore. The debut album called "Terast mis hangund me hinge" ("Steel frozen in our souls") was released at that time.
In 2000, a good friend Varulven joined the band. Thus far he had observed the activities of the band and had from time to time joined them on stage. Varulven had self-taught himself a number of ancient Estonian folk instruments and together it was realized that metal and old Estonian folk fit together perfectly. Since then, the music of Metsatöll has intertwined more and more with old Estonian runo-singing and traditional melodies.
2001 was a difficult year for the band, since their bass player Andrus left the band, deciding to attend more to his personal affairs, and considering the band too much of [......] ”

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