The short-lived Roman Empire always had bad luck with the Brythonnic Islands. Julius Ceasar's first expedition was a near-disaster, the second slightly more successful, but with no lasting impact. Later historians look back with nostalgia at the wise but all too brief reign of Caligula and his decision not to even attempt a crossing.
Many view Claudius's ill-fated expedition as the first nail in the Empire's coffin. In all, four whole legions were lost to storm and sea, with no survivors. Emperor Galba deposed Claudius, to the acclaim of the Senate. For a time his harsher policies semed successful, but his long struggle with the Flavians split the Empire, and before long all that remained were the few Eastern provinces ruled by Herod Agrippa. The old gods of Rome were forgotten, or merged with the gods of the barbarians.
It's possible that, if Claudius's fleet had landed, Rome could have subdued these islands. How long would that have delayed the inevitable?
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