The eleventh century is a period of profound political, social, and cultural upheaval in Italy, owing largely to the so-called “invasion” of the Normans who, initially offering their services to the highest bidder, ended up carving out their own polities in Apulia, Campania, and Sicily. This chapter will concentrate on military affairs in southern Italy between 1017, the year of the famous meeting with the Lombard rebel Melus, and 1077, which ended with the siege of Naples by the joint forces of Robert Guiscard and Richard of Capua.

The chief aim of the chapter is to examine the Greek and Latin narrative sources for this period, strictly from a military perspective, and to reach some conclusions regarding their value as sources for the Norman expansion in the South and the history of warfare in the Mediterranean in the eleventh century. The major questions that are raised are: to what extent are the figures they provide for army sizes reliable, both in absolute numbers and in the ratios given between cavalry and infantry? What is our chroniclers’ knowledge of the local geography where the military operations took place, and to what extent – if at all – were they familiar with the terrain of the battles or sieges, or with the campaign routes of the armies they describe? How accurate and detailed are their descriptions of castles and fortifications, and how far do their narratives permit the accurate reconstruction of chains of events, especially in regard to the battlefield manoeuvres of armies in action? Do we have enough information to reconstruct the Norman strategy of expansion in the different but interconnected operational theatres of Italy and Sicily?

An Introduction to the Narrative Sources

The primary sources that are examined for “military” evidence on the Norman expansion in the Mediterranean include mainly those authors who wrote in Latin, like Amatus of Montecassino, William of Apulia, and Geoffrey Malaterra. The first of these three is the author of the earliest of the three substantial narrative accounts of the conquest of southern Italy by the “peoples beyond the Alps” in the eleventh century, from its earliest stages in the 1010s to the death of Richard I of Capua on 5 April 1078. The History of the Normans was probably completed shortly after the death of Richard I, hence around 1078/79.