There are many collections of regional songs from the north.

Part of the reason why "southern" songs seem more popular is that vaudeville and before that minstrel shows would cater to romanticized songs about the south - performing for northern audiences.

Why are there so many POPULAR songs about Ireland and fewer about England? Again, it played to a certain audience that was looking for romance and nostalgia for another place. Instead of patriotic songs, these are songs that reach for the heart.