Justinian I was the last great conquering Roman emperor, who dramatically increased the size of his realm although he never actually led an army in person. His long reign (527-565) was devoted to the challenging project of _renovatio imperii_, that is the renovation of Empire. His was the will and vision behind campaigns that saw the reconquest of Rome itself and Italy from the Ostrogoths, North Africa from the Vandals, and parts of Spain from the Visigoths. These grand schemes were largely accomplished through the services of two talented generals, Belisarius and Narses, and in spite of the distractions of wars against the Persians in the east for most of his reign and the devastation caused by bubonic plague.

This is the only book available devoted to analysing all of Justinian's campaigns on the basis of the full range of sources. Besides narrating the course and outcome of these wars, Michael Whitby analyses the Roman army of the period, considering its equipment, organization, leadership, strategy and tactics, and considers the longer-term impact of Justinian's military ventures on the stability of the empire.