Tell me about Welsh music

I’ve been listening to the Pogues lately (thanks to Three and Out), and I just started reading the Mabinogion, which got me thinking - I’ve been exposed to a fair amount of Irish/Irish influenced music, both more traditional stuff and more modern, punk-influenced music (the Pogues, Flogging Molly, the Dropkick Murphys). However, as an American, I don’t get nearly as much exposure to traditional Welsh (or Scottish, for that matter) music, just because there aren’t as many people who identify with Welsh culture here.

So, my question is twofold: first, is there a distinct Welsh traditional music? Wikipedia pretty much just talks about Celtic music, but I’m wondering how much differentiation went on. Would I (as someone who’s never heard traditional Welsh music) be able to distinguish it from traditional Irish music? Anyone got any names I can check out?

Second, are/were there Welsh bands in a similar vein as the Pogues or Flogging Molly - that is, traditional feel, but way more upbeat and with some punk and rock influences? Again, any bands in particular?

From my experience reading credits rather than the lyrics in church, I’d say the Welsh had more effect on Protestant hymns than the Irish or the Scots.

And if cutting down a single ash tree doomed John Delorean, how much damage can appropriating an entire ash grove do?

Youtube videos:

Ar Hyd y Nos (All Through the Night, a traditional lullaby)

Cwm Rhondda (A hymn from the traditional song of the cantref of “How Green Was My valley”)

Ton-y-Botel (Best known as the setting for James Russell Lowell’s “Once to Every Man and Nation”)

Aberystwyth

Men of Harlech

Gwlad, Gwlad, pleidiol wyf i’m Gwlad (National anthem of Wales)

Another Day (A very contemporary piece, included to show that Welsh music is not purely traditional)

Myfanwy

Calon Lan

Cymru Fach

Sosban Fach

Duw It’s Hard

Arglwydd Dyma Fi

Awyrennau

How is that for an interesting mix?

I knew this but, despite their claim of being Norskies, my parish sings an awful lot of Welsh songs. I can only assume the pagan origins of those songs can be cancelled out by the Welsh being (nominally) Christianized at about the same time.

FTR, despite being portrayed otherwise in the film Zulu, at Rorke’s Drift the 24th (The 2nd Warwickshire) Regiment of Foot was half English, a third Welsh, and the rest indeterminate, and they probably did not sing “Men of Harlech.”

While music is a very important part of Welsh culture (my Welsh grandfather was greatly saddened that his son and grandsons can’t carry a tune in a bucket), there isn’t a distinctive characteristic that you’d recognize as instantly as Irish music (for instance). A great number of Christian hymns were written by Welsh composers, or based on traditional Welsh music.

Modern Welsh bands include Manic Street Preachers and Stereophonics, but they’re hardly representative of any “Welsh sound.”