My impression is that for much of the Medieval Period cities along the Rhine were most economically powerful places in southern Germany, whereas by the later Middle Ages cities to the East like Ulm and Augsburg had surpassed them. Is this right, and if so, what caused this shift?

by mrsaturdaypants

mrsaturdaypants

I can't understand how the road network might have improved to the point that those cities east of the Rhine could also prosper, but I don't quite understand why the cities on the upper Rhine wouldn't grow proportionately, much like the lower Rhine cities in the low countries. I feel like I must be missing some important factors.