looker-on
aka Thomas the Kraut
Might be Thomas Jackson.His nickname was "Stonewall" as he never took a backward step in battle even against all odds.
If so, I confess that I'd not heard of him, which would kick me out of the league of "people with a good general knowledge" as per your definition. Yet that's what I'm here for: to broaden my horizon. Even old geezers have not finished learning.