Vegetius' late Roman text became a well-known and highly respected 'classic' in the Middle Ages, transformed by its readers into the authority on the waging of war. Christopher Allmand analyses the medieval afterlife of the De Re Militari, tracing the growing interest in the text from the Carolingian world to the late Middle Ages, suggesting how the written word may have influenced the development of military practice in that period. While emphasising that success depended on a commander's ability to outwit the enemy with a carefully selected, well-trained and disciplined army, the De Re Militari inspired other unexpected developments, such as that of the 'national' army, and helped create a context in which the role of the soldier assumed greater social and political importance. Allmand explores the significance of the text and the changes it brought for those who accepted the implications of its central messages.

De Re Militari by Vegetius is the famous strategy book written in times of the Roman Empire. It explains how they organized their armies, battles, sieges, and war strategies. This is the complete official edition and it contains the 4th part (how to perform sieges, city defenses, and naval warfare) which is not included in commonly available basic editions. De Re Militari is essential to understand European strategy and war due to the fact that, besides describing the military might of Rome in practical terms, it was also used by generals and rulers in the next centuries and the Middle Ages to organize European armies, conduct sieges, reinforce castles, train soldiers, and conquer enemy nations. So much so that generals would be judged and measured in warfare skills by their knowledge and understanding of Vegetius.

De re militari (Latin "Concerning Military Matters"), also known as Epitoma rei militaris, is a work by the Publius Flavius Vegetius Renatus. The book casts light on the Roman warfare and military principles. It gives a presentation of the methods and practices in use during the height of the Roman Empire. The text was written in the 5th century. According to Vegetius, things like training of soldiers as a disciplined force, orderly strategy, maintenance of supply lines and logistics, quality leadership, and use of tactics and even deceitwere all extremely important to ensure advantage over the opposition. He also stressed the selection of good soldiers and recommended hard training of at least four months before the soldier was accepted into the ranks.

A 5th Century training manual for the organization, weapons and tactics of the Roman Legions. Vegetius's "De Re Militari" was the only major work of Roman military science to survive from classical times. It was widely studied in the Middle Ages and was a key source for Medieval warfare and siege tactics.

As a veteran campaigner, the Byzantine emperor Maurice (582-602) compiled a unique and influential handbook intended for the field commander. In this first complete English translation, the Strategikon is an invaluable source not only for early Byzantine history but for the general history of the art of war. Describing in detail weaponry and armor, daily life on the march or in camp, clothing, food, medical care, military law, and titles of the Byzantine army of the seventh century, the Strategikon offers insights into the Byzantine military ethos. In language contemporary, down-to-earth, and practical, the text also provides important data for the historian, and even the ethnologist, including eyewitness accounts of the Persians, Slavs, Lombards, and Avars at the frontier of the Empire.