Something I'd add to this thread is that there's a difference between this epic music and the classic music we know. Of course, this neoclassic, epic music, epic orchestral rock was influenced by classical music but the differences from Verdi's Requiem for example (which indeed, I find epic) are remarkable.
This new genre is often linked to movies' music and I think the beginnings start with Hanz Zimmerman, Two steps from hell and Globus(Immediate music). I don't know much about Zimmerman but I think the modern epic style can be traced in his compositions to around 2000-2002 (I don't think his style of epic music should be the main one to refer to). TSFH and Globus, on the other hand, can be traced to 2004.
Recently, I discovered this song from 1998 which sounds like modern epic music. More specifically this part.
Also, in the Chronicles of Narnia (around 2005 -2008), there's Here comes the king track which I believe is one of the most representative for this modern classic music, epic music. For me the epicness is amplified by the choirs, I think it is a key element in defining this new genre.
Lastly, there's Audiomachine, which was founded in 2005 but released albums after 2010. Personally, I think this is the most representative track for this genre Guardians at the gate, every track that wants to be identified as epic music should refer in one way or another to this one. I don't know exactly when this song was first used but I think it's around 2008, although in the album it says it's 2012.
+Audiomachine albums: Decimus, Magnus, Tree of life
-these I believe should be taken as a reference for this genre
P.S. Sadly, I don't have any musical background but I hope soon I'll learn the musical theory and play the violin which I wish greatly to know how to :D
I am more familiar with the forms of arts and their evolution. The epic music genre is my favorite since around 2012 and I want maybe to do some research and to write some studies on this subject