Or pretty much the only thing that made France awesome back then.
I guess he was shorter than the average Frenchman, then?
I don't know, to be honest. I've heard that the average Frenchman then was 5 feet, 5 inches, which would make him taller than average, but I don't have reliable evidence for that. He's usually pictured near his guards, who were picked partially based on their height, so it's possible he looked short in comparison, word got out to his opponents about that and his nickname, and they started telling people he was short to mock him.
Edit: Dammit, Agita.