I'm just thinking "Cousin Jack" is a very easy transformation from "Cousin Jan" if you're trying to 'decornishify' the word and pick a generic English sounding name. Could be why it became the common fib name people told their bosses when introducing other cornish people for employment? Maybe a stretch though, I'm just spitballing.
England and Wales in particular have a habit of losing the history of the countryside, and folk songs are one of the only ways it seems to persist. And I love how current artists are both falling back on their experiences but also doing their own research into old, forgotten tunes and songs to bring life back into them and make them relevant again.
Mawkin actually has a good song about cornish mine workers, "I Can Hew"
Solo singer-wise there's some great material to be found with current singers like Chris Wood or Nick Hart. And if you go back a bit there's some really interesting songs from people like Tony Hall (lots of Norfolk oddities) and Dick Gaughan (Scotland. Kist O' Gold is a great album).
I tend to know more about tune history than songs but songs do give you a lot of scope for reviving old music. I know Faustus, for example, take old lyrics and write new tunes for them to change the sound. It's a really exciting way of keeping the stories alive and maintaining their relevance for new generations.
"It was Cornish miners who introduced football to Mexico. The country’s first football club – Pachuca Athletic Club – originally comprised exclusively of Cornish mine workers. The Mexican League of Association Football was established in 1902. The first championship was played that same year and in the 1904-1905 tournament it was El Pachuca that won first place. To this day the city of Pachuca still prides itself as being the home of Mexican football."
Even if this may not be the most popular entry...