Just read something of potential further interest to you, from the book I mentioned, during my lunch break:
"Koga's [sic] music is said to provide a paradigm of Japaneseness in music, but Kogan himself was raised in colonial Korea and acknowledged that he had developed his style around the songs he heard laborers sing there. Even Yamaori Tetsuo, the stalwart defender of Hibari's essential Japaneseness, acknowledges the ongoing debate over whether enka might not best be considered an essentially Korean, rather than Japanese, genre."
And so on.
Bourdaghs has a blog here, in case you were not curious enough to google: http://bourdaghs.com/
More on a Korean connection to enka
"Koga's [sic] music is said to provide a paradigm of Japaneseness in music, but Kogan himself was raised in colonial Korea and acknowledged that he had developed his style around the songs he heard laborers sing there. Even Yamaori Tetsuo, the stalwart defender of Hibari's essential Japaneseness, acknowledges the ongoing debate over whether enka might not best be considered an essentially Korean, rather than Japanese, genre."
And so on.
Bourdaghs has a blog here, in case you were not curious enough to google: http://bourdaghs.com/
Rudipherous