This study cast s some light on Eusebius and his times by tracing, or trying to trace, modifications in his views as expressed in the Church History. Everyone agrees that such modficiations can be found in Books VIII-X. This study seesk to find them in the first seven books as well. It does not make much difference whether we are illuminating the first quater of the fourth century or, in addition, the last years of the third century. In either case our sources for the history of Christianity are so meagre that closer analysis can only prove helpful. And whether or not one agrees with every detail of the portrait of Eusebius that begins to emerge, it is at least a picture of a human being, neither a saint nor intentionally a scoundrel. Eusebius' work is imprortant not just because of the documents he used but because of the ways in which he used them. These ways illuminate the history of the Christian Church in one of its most important transitions, a transition in which Eusebius himself played a prominent part. -adapted from the concluding chapter