In this book, McEvoy addresses the remarkable phenomenon of the Roman child-emperor. During the late fourth century the emperor Valentinian I, recovering from a life-threatening illness, took the novel step of declaring his eight year old son Gratian as his co-Augustus. Valentinian I's actions set a vital precedent: over the following decades, the Roman West was to witness the accessions of four year old Valentinian II, ten year old Honorius, and six year old Valentinian III -- all as full emperors of the Roman world despite their tender ages.
Even though they were sons of emperors, the...