Aurelian was in many ways the most remarkable emperor of them all. He took over when the empire wasn't just on the point of collapse, but had actually split into three. It was far from obvious that it would ever be reunited, and was in severe danger of actually being overrun by barbarians. That Aurelian succeeded in getting the show back on the road is little short of miraculous.
A good solid podcast gives a great insight into this able soldier.