The Roman Near East in the Time of the Tetrarchy and Constantine I (AD 284-337)

After the defeat of Emperor Valerian in 260 and the usurpation of the Palmyrene empire in the 260/270s, Roman control over the Near East was shattered. Emperor Diocletian (284–305) instituted a new form of government, the so-called Tetrarchy. The provinces were resized, the army reorganized, and the border defenses were fortified. Emperor Constantine (306–337) continued his predecessors’ successful work, and it often remains difficult for scholars to clearly attribute certain reforms to either the period of the tetrarchs or Constantine. The eastern frontier remained a top priority for all (Eastern) Roman emperors in late antiquity. By adopting Christianity as his favored religion, Constantine laid the basis for a long-term development that influenced the course of history beyond late antiquity. His building policy laid the foundation for what is called the “Holy Land” with Jerusalem as its center.