Poor Gallienus, son of poor Emperor Valerian, if you had existed in an earlier era, who knows what might have come of you?  As it was, you had the bad luck of being born in the heart of the disastrous 3rd century, when the machine that was Rome careened down the tracks, no one at the helm, brakes shot, with the wheels coming off.  With the Rhine and Danube frontiers overwhelmed by a relentless barbarian tide, the new Sassanid Empire in the East under vigorous Shapur I clawing back ancient Persian lands, and an endless line of internal usurpers aiming for the throne, one can't help but feel sympathy for Gallienus - but does he belong in the hall of heroes if the world nearly ended on his watch?