Crisis of the Third Century (Roman Empire)

Timeline

1. 235–238Rome · LazioAlexander Severus was murdered by his troops on the Rhine frontier; Maximinus Thrax took the throne, accelerating military interference in politics and imperial succession, and openly exposing the power struggle between the Senate and the army.
2. 259–274Gaul and Palmyra · SyriaAfter Valerian's capture, breakaway regimes emerged in both east and west: the Gallic Empire controlled large parts of Western Europe, while Palmyra expanded under Zenobia, severely weakening central authority.
3. 270–275Rome · LazioEmperor Aurelian recovered the territories of Palmyra and the Gallic Empire, restored imperial unity, and built the Aurelian Walls; the crisis eased, though structural problems remained unresolved.