In the year 381 AD, Theodosius, emperor of the Eastern Roman Empire, issued a decree requiring all his subjects to pledge loyalty to the Holy Trinity of Father, Son, and Holy Spirit. This decree defined Christian orthodoxy and put an end to a lively and broad debate about the nature of the Deity, declaring all other interpretations as heretical. For the first time in a thousand years of Greek-Roman civilization, free thought was suppressed without question. Nevertheless, this political revolution, intended to bring internal cohesion to an empire under threat from the outside, has been erased from historical record. Instead, it is claimed that the Christian church had reached a consensus regarding the Trinity, which was proclaimed at the Council of Constantinople in 381 AD. In this innovative new book, Freeman argues that Theodosius' decree and the subsequent suppression of paganism not only ended the diversity of religious and philosophical beliefs throughout the empire but also created many theological problems for the church, which remain unresolved. Freeman concludes that the year 381 AD was 'a turning point forgotten by time'.