Germanic Invasions During the Crisis of the Third Century

Between 235 and 284 CE, some fifty emperors or would-be emperors rose and fell, most by violence. This political chaos made coordinated frontier defense impossible. On the Rhine, the Alemanni emerged and began raiding across the river from the 230s onward. In 259-260 CE they broke through the limes and raided into Italy. The trans-Danubian portion of the limes was permanently abandoned around 260 CE. The Franks raided into Gaul and Hispania in the 260s. The empire responded by creating the breakaway Gallic Empire (260-274 CE) under Postumus. Most dramatic was the Gothic incursion across the Danube. In 251 CE the Gothic king Cniva defeated and killed the Emperor Decius at the Battle of Abrittus, the first Roman emperor to die at the hands of a foreign enemy. The empire survived only through the energetic reign of Aurelian (270-275 CE), who reunified the fragments and built the Aurelian Walls around Rome.

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