Tell me about the blues: Did they originate in New Orleans?

In a recent post Ted Gioia considers the possibility that the blues originated in New Orleans. After considerable discussion:

All this is significant and enlightening, but insufficient to prove that New Orleans was the birthplace of the blues. But it does suggest that blues was a significant ingredient in its commercial music scene at a fairly early stage. My considered judgment is that New Orleans was the source of “blues-inflected jazz”—but that’s a very different claim than citing it as the home of all blues. And as all the available evidence shows, early jazz ...