The Carolingians regarded much of Italy as a military frontier following their overthrow of the Lombard kingdom in 776. Although there was little national Lombard resistance to Frankish rule, other factors — which will be noted later — forced the Franks to keep up their military establishment in Italy. In some ways this military establishment followed the pattern of Carolingian arrangements in other conquered territories, in other ways the Italian situation was quite unique. Since the Carolingian failure to solve the problem of Italian unity was in at least a degree due to the Carolingian failure to meet the challenge of the Italian military frontier, the study of this problem throws some interesting light on the turbulent conditions in northern and central Italy before and after its incorporation in the German Holy Roman Empire.