The council of bishops that met at Nicaea, in what is now northwest Turkey, in the spring of the year 325 provides wonderful opportunities for any historian concerned with the human situation. Later generations referred to it as the first ecumenical council of the Christian church. They revered its decisions and regarded them as permanently valid. Many churches still say or sing the Nicene Creed. More historically, it marks the end of early church history and the dawning of the Middle Ages. There was a fundamental change in church-state relations. For centuries Roman emperors had intermittently persecuted Christians; now the Roman emperor took his seat among the bishops and discussed theology with them. As we begin to investigate the historical situation, however, we immediately encounter problems like those faced by all who try to check up on the activities of kings and other rulers. The official mythology, so to speak, does not always correspond to the facts. The Council of Nicaea was ecumenical only in the sense that the participants came from the Roman world and, indeed, only from the eastern half of it. Much of the council's work came unglued within a year or two after it ended. The so-called Nicene Creed was actually set forth not at Nicaea but at Constantinople in 381. The emperor's activities at the council were not an unmixed blessing. Beyond these points, with which we shall deal somewhat more fully, lies the remarkable fact that the official irecord of the council disappeared almost at once. Within twenty-five years a leading participant in the council wrote a book about it and had to rely on his memory for an account of what went on. To put it another way, the tapes of the council's proceedings were definitely not available.