Dr. Justo Gonzalez's "Story of Christianity, 1: Ch.12: Great Persecution...

Chapter 12. The Great Persecution and the Final Victory, 119-126. During the reigns Decius and Valerian, the Christian enjoyed relative peace. But, things would change with Diocletian. Diocletian creates a four-fold team of emperors—Galerius under Diocletian (the superior) and Constantius Chlorus under Maximian (another superior). Ultimately, this is an unstable mix. Galerius was unhappy about Christians in his army and, fearing disloyalty, had some killed. Galerius increasingly was anti-Christian. He convinced Diocletian to engage in increasing persecution—no place in government, confiscation of properties and books, and, finally, an order that all Christians must offer sacrifices to the Roman gods. Mixed results on that one. In all the political turmoil, Constantine of Gaul and England, becomes the new Augustus or new Caesar in the famous battle of the Milvian Bridge. The conversion story is told by 4th century church historians, Lanctatius and Euseubius. The famous Edict of Milan, 313 A.D., is issued and, over time, there are no more persecutions. The church will emerge from the shadows and come to enjoy increasing pomps and eases under Constantine, a theme for later development.