Clannad were cool when they were making actual Celtic music (as opposed to Celtic Muzak™). Anything up to and including Fuaim is guaranteed good, though.
There’s lots more “contemporary Celtic” groups worth listening to (Planxty, De Danann, Bothy Band, Moving Hearts etc.). Horslips is probably my favourite as they’re the most rock oriented (basically a rock band with Celtic themes instead of the other way around). For the Scottish version, try Runrig.
The Italian duo/project Narrow Pass have a definite Celtic bent but they’re more a folk-progressive band with Celtic flourishes really.
Loreena Mc Kennitt...A great starting place. I would compare her to Enya but her music's got a lot more pep than that. Also, she puts on a great live show.
If I were to write some of the strange things that come under my eyes they would not be believed. ~Cora M. Strayer~Much like the Celtic Reconstructionist religion does the old Irish lore, I'm necroing the fuck out of this topic.
So, Celtic is great. It's actually because of Celtic music (and soap, long story) that I started learning about my ancestry, not the other way 'round- shows how much I love it. In particular, I greatly enjoy Celtic-and-something (Rock and Metal, usually, though Dalriada's Celtronic is pretty legit) blends and Prog Rock/Metal with Celtic influences. I think what makes Celtic music great is the way it blends surprisingly well with. . . Well, pretty much everything.
Mura: -flips the bird to veterinary science with one hand and Euclidean geometry with the other-For reference: http://m.myspace.com/home.wap?bfd=webnext&isredirected=true#friends.list/profile/46507086
(I googled the name of one of their songs, so yeah)
Mura: -flips the bird to veterinary science with one hand and Euclidean geometry with the other-Ever hear Celtic Woman? It's a great big orchestral group with a lot of different singers doing different songs.
And actually, in their heyday the Celts stretched from Northern Spain all the way into Romania, so most of that European Folk Music is related to Celtic as well. The Northern and Western parts of the British Isles are just the Celts' obvious last stand, so we think of Ireland and Scotland first. So with that, I'll add Omnia and Faun to the list of Neoceltic glory.
On the topic of non-British Isles Celtic music, I freaking love Xera. Celtronica from Astures, Spain.
Afro Celt Sound System is also good stuff.

I just watched The Secret Of Kells and would like to continue listening to Celtic music. Preferably with a slightly modernist bent, since I seem to enjoy Genre-Busting, but it's all good. Can anybody help me out here?
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