Ah! Definitions of Folk!
The Anglo-Saxons had communal story/poem/song. Some were to celebrate the memory of a leader. Some to educate the tribe. How far back should we go to find evidence?

Take "Bunch of Thyme" - clearly an educative moral tale.
"A trouper Watering his Nag" - a joke. Or an ad for the Tavern trade.
They had butter-making shanties to time the turning of the drum see also "Spinning Wheel"
And I give Waulking songs.

Not exactly solitary songs, though the "shanties" might be described thus. Sea shanties definitlely weren't.