Sorry I started and didn't finish.

Regarding protest songs, there are of course the "gutter choir" songs which were born out of mining disputes.

I'm sure Dr Price will have more to say on the matter, but two examples I know: A Miner's Life, which in this area is sung to the tune Calon Lan, it later got set in the US to Life Is Like a Mountain Railroad, which is the more commonly known version in the UK; also When the Coal Comes From the Rhondda to the tune When They call the Roll up Yonder.