Tetrarchy: Did you mean...?

The First Tetrarchy (293–305 CE) was Emperor Diocletian's (reign 284–305 CE) solution to the political and military crises that had nearly destroyed the Roman Empire during the Crisis of the Third Century (235–284 CE). Following decades of...

This map illustrates the geopolitical situation in the Levant after the death of Herod the Great (ruled 37–4 BCE), the ambitious client king of Judea appointed by the Roman Senate. His death marked the breakup of his kingdom into the Herodian...

Diocletian was Roman emperor from 284 to 305 CE. After the defeat and death of the Roman emperor Philip the Arab in 249 CE, the empire endured over three decades of ineffective rulers. The glory days of Augustus, Vespasian, and Trajan were...

The Roman Empire, at its height (c. 117), was the most extensive political and social structure in western civilization. Building upon the foundation laid by the Roman Republic, the empire became the largest and most powerful political and...

Galatia was a region in north-central Anatolia (modern-day Turkey) settled by the Celtic Gauls c. 278-277 BCE. The name comes from the Greek for "Gaul" which was repeated by Latin writers as Galli. The Celts were offered the region by the...

The Roman army underwent dramatic changes in Late Antiquity. Civil war and external conflicts led to the creation of new legions while existing legions were either split or disbanded. Although there was an increase in the number of legions...

Porphyry sculpture portraying the four Tetrarchs (Diocletian, Maximianus, Galerius and Constantius Chlorus) embracing. It is dated to c. 300 CE and was sculpted in Asia Minor. It probably originally decorated two separate pillars in Constantinople...

The Crisis of the Third Century (also known as the Imperial Crisis, 235-284) was the period in the history of the Roman Empire during which it splintered into three separate political entities: the Gallic Empire, the Roman Empire, and the...

Built in the seventh century BCE, the ancient city of Byzantium proved to be a valuable city for both the Greeks and Romans. Because it lay on the European side of the Strait of Bosporus, the Emperor Constantine understood its strategic importance...

The Western Roman Empire is the modern-day term for the western half of the Roman Empire after it was divided in two by the emperor Diocletian (r. 284-305 CE) in c. 285/286 CE. The Romans themselves did not use this term. At its height (c...