A compelling biography of Constantine I’s heir: “Excellent analyses of a number of battles and sieges . . . a good read for anyone interested in the late Empire.” —The NYMAS Review   The reign of Constantius II has been overshadowed by that of his titanic father, Constantine the Great, and his cousin and successor, the pagan Julian. But as Peter Crawford shows, Constantius deserves to be remembered as a very capable ruler in dangerous, tumultuous times.   When Constantine I died in 337, twenty-year-old Constantius and his two brothers, Constans and Constantine II, all received the title of Augustus to reign as equal co-emperors. In 340, however, Constantine II was killed in a fraternal civil war with Constans. The two remaining brothers shared the Empire for the next ten years, with Constantius ruling Egypt and the Asian provinces, constantly threatened by the Sassanid Persian Empire. Constans in turn was killed by the usurper Magnentius in 350. Constantius refused to accept this fait accompli, made war on Magnentius, and defeated him at the battles of Mursa Major and Mons Seleucus, leading Magnentius to commit suicide. Constantius was now sole ruler of the Empire—but it was an empire beset by external enemies.   This historical biography recounts Constantius’ life and his successful campaigns against the Germanic Alamanni along the Rhine and the Quadi and Sarmatians across the Danube, as well as his efforts against the Persians in the East, which had more mixed results—and reveals how he defended the Empire until his dying day.