...most likely the first minor key polka coming to my knowledge...
But getting back to major, minor, and such... I just did a quick breakdown of those 101 polkas by "mode", and came up with the following:
- Mixolydian: 0 (that surprised me; I'm sure there are some, even if not in that book)
I've just checked Mallinson's 100 Irish Polkas and found plenty of minors but just three and a half mixolydian (Plus a couple more that have the odd flat seventh). Not dissimilar from your finding, Jim.
Could it be because they're relatively late arrivals into British traditions and often from the professional stage? Mind you, traditional players must have been churning them out in Sliabh Luachra and elsewhere. Maybe the mixolydian mode doesn't match the jauntiness of a polka??? I dunno. Interesting! Might try recording them tomorrow.