When I think of "folk metal," I think of the scene in This is Spinal Tap with the dwarf dancing around the tiny Stonehenge. This is because I'm incredibly immature. The term is actually used to define any metal band that incorporates its country of origin's indigenous sound within their own. Within this framework, Enslaved, Bathory and later year Burzum could be construed as "folk metal". Add to these, Ireland's Primordial, a band that's been around for almost twenty years but still have never really gotten the credit they deserve. Sure, they aren't the most prolific - they're starting to exhibit Metallica-like length in between albums, but you can't rush a good thing.
To the Nameless Dead is a natural progression from their previous efforts - with sweeping, majestic stories told through dense guitarwork, solid production (although a little too much high-end in the mix for my liking) and using their national pride as a driving lyrical influence without succumbing to the rhetoric of their lesser peers. "Heathen Tribes" and "As Rome Burns" has the tom-heavy rhythms of a hundred bodhráns leading the charge into battle. The Celtic sound has crossed over well into punk music over the years but crossing over into metal has been long and winding road. Here, it works.