Totila enjoyed several advantages: the outbreak of the Plague of Justinian devastated and depopulated the Roman Empire in 542; the beginning of a new Roman–Persian War forced Justinian to deploy most of his troops in the east; and the incompetence and disunity of the various Roman generals in Italy undermined military function and discipline. This last brought about Totila's first success. After much urging by Justinian, the generals Constantinian and Alexander combined their forces and advanced upon Verona. Through treachery they managed to capture a gate in the city walls; instead of pressing the attack they delayed to quarrel over the prospective booty, allowing the Goths to recapture the gate and force the Byzantines to withdraw. Totila attacked their camp near Faventia (Faenza) with 5,000 men and, at the Battle of Faventia, destroyed the Roman army. Totila marched into Tuscany, where he besieged Florence. The Roman generals, John, Bessas, and Cyprian, marched to its relief but, at the Battle of Mucellium, their numerically superior forces were defeated.