For the church historian, there is perhaps no more baffling problem than to account for the union that was effected between Christianity and the Roman State. The acceptance of this new religion by a government bound up with the heritages and customs of a thousand years of heathenism would be an astounding phenomenon were it not already so familiar to the historian. Scarcely less perplexing is the corresponding transformation in the attitude of Christians toward the Roman government. It seems almost inconceivable that a religious movement, which began with the conviction that “all the kingdoms of the world and the glory of them” were the proper possession of Satan, should ultimately hail with approval a union of Church and State. There is no need to rehearse the course of events that marked the gradual rapprochement of Christianity and the Roman State. That story has been well and frequently told. But the genetic forces operating in that ancient society to bring about this remarkable result, still await further analysis. It is in this particular field of research that our present study falls.