Welsh mining songs - "Merthyron y Glo", Niclas y Glais (TE Nicholas)
(Chwi ddewrion y dwfn erwau tywyll...)

Also, from Kent is "Garden of England":-

To the garden of England strangers came one day
From the north to work down the mines.
To the garden of England strangers came one day
And they walked hand in hand with their wives.

And the children played in the green fields
And sang their songs, and danced away the years,
Coming home, kicking leaves by the roadside,
Coming home, walking hand in hand.

To the garden of England strangers came one day
Riding horses down narrow country roads.
To the garden of England strangers came one day
Linking arms and forming battle lines

And the children (etc.)

In the garden of England our children play games
Linking arms and forming battle lines.
In the garden of England our children play games
Of police facing picket lines

And they play no more in the green fields
Or sing their songs, or dance away they years.
Now they all link arms by the roadside,
Facing strangers, forming battle lines.

To the garden of England strangers came one day
Driving horses down narrow country lanes.

Sorry - but I've fogotten who wrote it. All I recall is that she was married to a Kent miner.