They originated in the lower Elbe valley. The Lombards played little or no part in the overthrow of the West Roman Empire. Under Audoin, they became federates of the Empire after the year 540. Under the terms of this agreement, they assisted Justinian in his wars against the Ostrogoths and Franks forming the core of Narses’ centre at the Battle of Taganae.
Conquest of Italy
In 568, Alboin led a host of Lombards, Gepids, Sarmatians, and other peoples. As they advanced, the vacuum left behind them was filled Avars, Bulgars, and Slavs. Aqueilia and much of the Venetian plain was quickly seized. Within a year they had taken control of Milan and were largely in control of the Po Valley. They reached Rome in 575. For the next decade after Alboin's murder, the Lombard were ruled by an alliance of traditionally 35 duces. For a whole generation the Lombard behaved in the worst traditions of barbarian conquerors; murdering landlords and seizing their lands, plundering the countryside and taking the city for themselves. The emperor was powerless to intervene. Justinian had achieved replacing the stable Ostrogoths with a barbarian anarchy.