In a discussion at TheOneRing.net's forums, JRandomRohirrim commented that there was a phrase in Arrigo Boito's Prologue to Mefistofele that sounded quite similar to the music heard as the Ents rip apart Isengard. I checked the cd out of my library to have a listen. JRandomRohirrim directs us to about 3:15 into the final movement of the prologue, (Final Psalmody). I could hear the similarity that JRR heard, but I heard more. Earlier in that movement, one can hear singing much like that that is heard as Gandalf/Olórin reveals himself in Fangorn Forest, (The White Rider in Nature theme). I realized that both the Ent music and the Olórin music had similar rising phrases. Let me break this down into the two comparisons.

Olórin Revealed

This is the music heard when Gandalf reveals himself as the White Wizard in Fangorn. The lyrics contain two parts. One part is sung slowly, two syllables per measure. It is this part that slowly ascends. The other part is sung in faster triplets, two sets of triplets for every slow note sung. This music was originally intended to be used for Gandalf's arrival at Helm's Deep. It would make sense, therefore, that HS has tied this music and the Ent Attack music together with similar rising phrases.

In Boito's fourth movement of the Mefistofele's Prologue, one can hear this same motif: a slowly sung, ascending phrase paired with faster triplets.

	Boito's Mefistofele, part 1 - 1:11-1:20
	Boito's Mefistofele, part 2 - 1:30-1:39
	Boito's Mefistofele, part 3 - 1:48-1:58
	Olorin Revealed, part 1 - 0:19 - 0:28, TTT, Track 16, Forth Eorlingas

Ents Attack Isengard

The phrase JRandomRohirrim pointed out as sounding similar to the Ent Attack music continues the ascending nature heard earlier, but without the triplets. In my head, I could hear soundtrack music as I listened to Boito, but I wasn't happy with my attempt to match it to a section of the Ent Attack music for comparison. I think I finally figured out why. The soundtrack music evoked as I listened to Boito wasn't the Ent Attack music, it was the Olórin Revealed music. To my ears, there just as much similarity (if not more) between the rising notes of the Olórin music and Boito as there is between the Ent music and Boito. I happily provide a comparison between all three pieces and let you decide what you think.

	Boito's Mefistofele, part 4 - 3:16 - 3:55
	Olorin Revealed, part 2 - 0:28 - 0:59, TTT, Track 16, Forth Eorlingas
	Ents Attack - 4:00 - 4:21, TTT, Track 17, Isengard Unleashed (although I suggest you listen to this entire section on the soundtrack cd)

All the Boito clips are from a recording by the Atlanta Symphony Orchestra & Chorus under the direction of Robert Shaw.