Check out this treaty map from 1760! The river near the top of the image is mapped as the "Hogohegee". The note in the bottom right corner identifies the area as being between Lattitude 34 and 36.
There are many on line resources that I have discovered. I hope I can figure out how to share them through this site!
Double click on the map to get a closer look. Once you double click on it you can move around on the document to really see it well. Check it out!