Third-century crisis

The third-century crisis is a term used by historians to describe the political, military, and economic turmoil of the Roman Empire in the third century A.D. Frequent changes of rules, barbarian invasions, decline or urban centers, and the near destruction of long-distance commerce were all parts of this condition. It ended in 284 when Diocletian restored order by making fundamental changes in the Empire.

Sources

The Earth and Its Peoples A Global History, Bulliet et al, 2005.