This above map depicts the dioceses and provinces of the Roman Empire following the restructuring of Diocletian. Principal settlements of the period are also labeled. | Emperor Diocletian Lived from c. 245 to c. 312 A.D. Roman Emperor from November 20, 284 to May 1, 305 A.D. | Emperor Constantine (also known as Constantine I or Constantine the Great) Lived from February 27, 272 to May 22, 337 A.D. Roman Emperor from 306 to 337 A.D. | |
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