When I attempted to add some information to "Background of Brother Ephus," thread 48470 Ephus and thread 9197 "Uncle Ef's" Uncle Ef's
I found that I was quoting from references to minstrel shows, upstart crow humor, Negro songs and Negro spirituals, and antecedents of blues. They can't be separated.

It is difficult to discuss just this one song without much study. I hope others will add to my brief comments. This one rather puny song shows the interrelationships pointed to by WYSIWYG's question, "What are the connections....?"

Minstrel and Negro music, exclusive of true spirituals, of the period 1830-1900 (arbitrary dates) are so intermixed that no clear divisions can be made at this remove. For the period ca. 1900-1940, ragtime and blues are added to the pot au feu.

Butch can do a better job of explaining these intimate relationships, but it is obvious, at least to me, that OUR music (both whites and blacks have contributed) cannot be explained without knowing the historical background.
Some object to dialect. Why? Both whites and blacks, in the rural areas from which many these songs sprung, were not educated to NY-Boston upper class standards and dialect was common to both.
The words nigger and coon appear in hundreds of completely Negro songs. Should these songs be eliminated as well as the minstrel routines?
Jokes at the expense of the poorly educated and the downtrodden were common to all groups in the 19th century (and persist in the redneck, hick, etc. jokes). Some famous politicians made their reputation by exploiting these jokes. Should we be ignorant of this?