Reign of the cruel and corrupt Roman Emperor Caracalla.
Caracalla grants citizenship to communities throughout the Empire.
Ardashir overthrows Ardavan, the last of the Parthian kings, and founds the Sassanid Dynasty, ruling a new Persian Empire. Zoroastrianism becomes the state religion.
The Sassanids, descended from the Achaemenids (see Cyrus the Great 558 B.C.E.), maintain the Persian Empire and hold off the Romans until defeated by Arab warriors.
As the Roman Empire comes under increasing threat, the political tensions in Rome also increase.
The beginning of the Axum Empire in Ethiopia, which will have prosperous cities along the major trade route of the Red Sea.
The Goths invade the Balkans.
The Roman Emperor Valerian (193 to 260) is defeated by Shapur of Persia at Edessa and dies in captivity.
Queen Zenobia of Palmyra conquers parts of the Roman Empire in the Middle East.
Emperor Aurelian, who rose from being an ordinary soldier, abandons Dacia (northwest Romania) to the Gothic tribes.
Roman Emperor Diocletian reorganizes the empire, dividing power between himself and three others (the Tetrarchy). Christians suffered much persecution during his rule.
In the face of the growing number of attacks on the empire, Diocletian divides it in two. He appoints Maximian as his co-emperor to rule the western half, while he rules the eastern half.
The martyrdom of St Maurice and the Theban Legion.
The Roman Empire declines in the face of barbarian incursions.
Stirrups are invented in China but would take time to reach Europe. Mounted warriors can now use swords and spears more effectively on horseback.