The Normans came into contact with the Byzantine Empire in the 11th century. They were first invited by the Lombards in Italy to help them fight against the Byzantines. In time, Normans were able to create a stronghold for themselves in southern Italy. By 1040, Normans had also forged ties with Byzantines and were serving as prominent mercenaries in Byzantine campaigns. They played an important role in the Byzantine conquest of Sicily.
Towards the late 11th century, the Normans had gained enough power in Sicily to drive out the Byzantines and secure the island for themselves. The Normans also began attempts to conquer the Balkans in opposition to the Byzantines. Although these attempts continued through the 11th and 12th century, they had little permanent success in the Balkans against the Byzantine control.
The Normans originally came into contact with the Byzantine Empire when they were invited by the Lombards to help them. However, they had soon switched sides and became mercenaries serving Byzantine military in the 11th century. During this period, Normans served in Byzantine service in regions as far and diverse as Antioch, Georgia and Trebizond. They also first served under the Byzantines in southern Italy before deciding to venture on their own.
William Iron Arm was among the notable Normans of the time. He created his own dominion in the regions of Apulia and Calabria in the 11th century, wresting the control away from all other contenders in the region including the Byzantine Empire. Normans also gained significant influence in Byzantine Greece. However, Normans soon began attempts to establish their own dominions in opposition to the Byzantine Empire and were consequently pitted against the Byzantine Empire.
From 1038 to 1040, the Byzantine Empire attempted to capture Sicily from Arab control. Norman mercenaries played a prominent role during this campaign. Although the Byzantine campaign which included Normans and Lombards was initially successful, it soon disintegrate due to dissension.
Later, Normans took it upon themselves to conquer Sicily. As a result, the Normans were soon able to establish their own rule not only in southern Italy, defying the Lombards and the Church, but also in Sicily defying the Byzantine Empire.
Normans originally fought briefly against the Byzantine Empire before becoming mercenaries under the Byzantine Empire in the 11th century. It was during this period that Normans ranged out from their original homeland in Normandy to different regions of Europe.
This was primarily fuelled by the relative lack of resources and wealth in Normandy, which also explains Normans’ attempts to seek mercenary service in different regions. Although they served the Byzantine for a few decades, the Normans soon sought to create independent dominions in regions which originally fell under Byzantine influence. This pitted the Normans against the Byzantine Empire, a conflict in which the Empire sustained most of the losses.
Normans were successful in creating their own sphere of power in southern Italy, including Sicily. They even ranged far into the Byzantine Empire, such as in the regions of Dyrrachium, but couldn’t establish a firm foothold in the mainland of the Empire.