Daughter to one emperor, half-sister to two more, wife to a Gothic king, then a Roman general, and mother to yet another emperor, Galla Placidia Augusta (c. 388–450) was at the heart of the Christian dynasty of Theodosius i. Joyce Salisbury's new biography, which joins those of Oost (1968, now rather outdated) and Sivan (2011), takes the positive view of female imperial power advanced in Holum's study of the Theodosian empresses (1982). She explores the diverse facets of a career which spanned the decades which saw the collapse of the Western Roman Empire, and which is of significance both for the history of women in power and the evolution of the architecture, institutions and doctrines of the Christian Church. From the accession of Theodosius i in 379, Placidia's story is traced through her residence at Rome as a child down to the fall of the city in 410 (pp. 6–63); her sojourn as a hostage with the Goths and her marriage to their philo-Roman king Athaulf in 414 (pp. 64–111); the murder of Athaulf, her second marriage to Constantius iii and the birth of their son Valentinian iii (pp. 112–38); her period of power in the West as the guardian of her young son (pp. 139–73); her last years (of which little is known) and her peaceful death (pp. 174–200). A devout Christian, Placidia corresponded with Christian clergy and took an interest in ecclesiastical controversies. She was also an active builder, for example of the basilica of St John the Evangelist at Ravenna and its associated library (pp. 150–2). Salisbury's heroine is set in the wider context of the military, political and social history of the time and the many gaps in the record are filled with racy accounts of the customs of the Goths relating to food and dress, or the processes of Roman childbirth, as recounted by instructors of midwives, or the landscapes that Placidia would have encountered on her journeys. Salisbury's narrative is also shaped by her sympathetic awareness of emotion. While inevitably speculative, she hints at Placidia's romantic preferences through her comparison of the handsome (if short) Athaulf with the dour and unprepossessing Constantius; more poignant was Placidia's choice, in 450, to be buried with Athaulf's baby son, who had died in infancy thirty-five years before. Some however may disagree with Salisbury's perspective on the power of the fifth-century empress. It does not detract from Placidia's achievement that her freedom of action was institutionally limited; crucially (pp. 147–9), Salisbury ignores the central role of the quaestors, the top imperial officials who created the texts and often the substance of laws. While power, as the Romans knew, came in many forms, and was exercised through a constant process of negotiation, Placidia could have recollected what Ambrose (and others) had said, that the toughest contests bring the greatest rewards.