Justinian is one of the best documented Roman emperors, not least thanks to the splendour of Procopius' Histories. These shed welcome light on warfare in the Late Roman Empire, especially because Procopius himself had been involved as Belisarius' secretary in his first campaigns against Vandal Africa and Ostrogothic Italy.
Already in the preface of his Procopius singles out the archers of his day as not one bit inferior to Homer's heroes. They were armoured, carried swords and spears, and fought on horseback, thus forming highly flexible units. Some historians have questioned this odd blend of heavily armoured lancers and horse-archers. Yet mounted shock troops and archers became the leading branches of Eastern Roman armies. With much fanfare, Procopius claimed that Belisarius had conquered Vandal Africa "with 5000 horsemen". Later, when Belisarius held out during a year-long siege of Rome against the Ostrogoths, Roman citizens marvelled "how one man's household was destroying the power of Theoderic" (founder of Ostrogothic Italy). Both times, a key role was played by probably the only men capable of blending the part of mounted archers and lancers: the In the Justinianic era, these men were elite soldiers who accompanied commanders, officers, and ministers as guards and special forces. Yet their origins are shrouded
