Justinian I: Biography of the Byzantine Emperor, Justinian the Great

One of the most prominent aspects of Justinian's renovatio imperii was the partial reconquest of the western provinces of the fallen Roman Empire. His military campaigns, led by the brilliant general Belisarius, achieved remarkable successes. Belisarius swiftly captured the Vandal Kingdom in North Africa, establishing Byzantine control over the region. Shortly thereafter, he, along with other generals like Narses, waged a series of successful campaigns against the Ostrogoths in Italy, eventually reclaiming key territories such as Dalmatia, Sicily, Rome, and much of Italy. This marked the end of the Ostrogothic Kingdom, which had ruled for over fifty years. Additionally, under the leadership of the praetorian prefect Liberius, the Byzantines reasserted control over the Iberian Peninsula, establishing the province of Spania. These victories re-established Roman dominance in the western Mediterranean and brought in substantial annual revenues, estimated at over a million solidi.