I know I heard a radio programme about dialect poets a short while ago, and here is a relevant link:

http://www.bbc.co.uk/programmes/articles/4xDyV5CQKLMDPcrnyWMBLj8/an-ear-for-an-aye-listening-to-englands-dialect-poetry

I also foundsomething about the cotton famine poets on the BBC web site, and here is a link:

https://www.bbc.co.uk/news/uk-england-lancashire-37836654

These people were mostly poets not song writers, though.