Johnson Family Tree Expansion

Greetings all, I am trying to go back further in my family tree along the Johnson line. I cannot seem to find anything further than my great grandparents: John Marshall Johnson and Beaulah Francis Johnson (nee Smith). I have found 1 or 2 great grandparents but the information is so limited I was hoping that someone within our family tree might be able to shed a bit more light on the subject: date of births, places etc.

Here's hoping!