It is a great time to be a fan of both the Classical world and heavy metal music: the two have never overlapped to the extent that they do right now. Consider, for example, the fact that in 2013 not one but two Italian metal bands, Heimdall and Stormlord, released concept albums based on Vergil’s Aeneid.
But this overlap is not a new phenomenon—in fact, far from it. Heavy metal music has drawn on the Classical world almost from its very beginnings, and this interest in the Classical world is part of a larger obsession with other times and places—both real and imagined— that is a defining characteristic of the genre. And since metal is a conservative genre (there are clear forefathers to whom almost all subsequent bands owe and acknowledge their allegiance), the interest in these kinds of subjects by earlier bands sanctioned continuous use of them by all subsequent bands.