A piece of history, or so I claim. I have thusly declared this single CD the beginning of the symphonic metal genre. So say I, alas.
It's of course hard to pinpoint the exact beginning of any genre since everything is based on something older and I'm pretty sure no one ever comes up with something entirely new entirely out of nowhere (even if popular narratives like to claim otherwise because it's more entertaining that way).
Okay. But. Therion's Theli (1996) album is the album that is most frequently cited as the first "real" symphonic metal album. However. There are at least 2 albums that came out the same year, a few months earlier, that might also qualify for that position - Waltari's Yeah! Yeah! Die! Die! and Rage's Lingua Mortis. But I find those albums unsatisfying for the position. Waltari are generally a crossover act that does a little bit of everything and didn't really commit to the symphonic concept - even some of the tracks on the album aren't very symphonic at all. And Rage are also more incidentally symphonic (though they kept returning to it, like at this Wacken concert with orchestra), also the Lingua Mortis album isn't very... metal. It's more a metal band doing a neo-classical album. Whereas Therion a) balanced symphonic and metal and b) really committed to the concept and stayed with it.
So okay, let's say for the sake of convenience that Therion's previous album Lepaca Kliffoth (1995) was the first symphonic metal album then. That one came out before all that Rage and Waltari stuff, and it already has symphonic aspects on some tracks, most notably both a male and a female opera singer. But really that's only on three tracks, and the bass-baritone is even only on two tracks, and most of the rest is either "a little" symphonic or "not really at all".
So what's the perfect compromise? I will unilaterally crown the Beauty in Black single the birth hour of symphonic metal. It includes both the tracks with the soprano and the bass-baritone - the title track and the awesome Evocation of Vovin with its high-speed synth-string beginning. And it came out in August 1995. Assembling all the most symphonic tracks on a CD shows much more of a symphonic concept than having them on an album with some less symphonic ones.
And I just like the thought that the genre of symphonic metal, the one with the operatic singing and the large orchestras, was announced by a track called "The beauty in black", and even before that, the intro "Arrival of the darkest queen". It's just so epic! It's a little arbitrary, but it feels really satisfying.
And now I own the CD, hell yeah!
Also, fun fact that I only just learned: The soprano, Claudia-Maria Mokri, also sings on Celtic Frost's "To Mega Therion" album, which the band Therion was named after!