1. Johnny St. Cyr didn't play the tenor banjo. He played 6-string banjo tuned like a guitar.
2. A mention of Taj Mahal should be here. He won the Topanga Canyon banjo and fiddle contests for a couple of years in a row and his score for the movie Sounder features his banjo playing.
3. The separation between the four-string and five-string is a recent development. Early string band groups used both. The Georgia YellowHammers come to mind. Also,
in North Georgia white groups as well.

It has become a question as to whether the white Minstrel show entertainers actually wrote some of the songs they are noted for, such as Daniel Emmett with Dixie and Old Dan Tucker. The banjo was not as popular as the fiddle on the "plantation" however many of the tunes emanated from the slavery times. Did these entertainers copy what they heard from Black slave tunes? You can't always determine the origin of a song from its printed copyright.

The important thing to remember about the banjo is that it has until recently been a dance music instrument because of its rhythmic percussion. Bluegrass changed some of that but in the process left some of the idiosyncrasies of the banjo and its sound.

According to Karen Lin, "The Half-Barbaric Twang", the banjo crossed over into Appalachia because of the exposure of the instrument in the traveling show, Uncle Tom's Cabin. This was seen all over the South.

Uncle Dave Macon popularized the Minstrel Show style comparatively recently on the Grand Old Opry. Many of the songs of the Hoe-downs and "set-runnings" had roots in the early Minstrel Shows such as Cindy, Angline the Baker (Angelina Baker), etc.