"... sorry, is this a bad decade? Should we invade later?"

Explanation: The Roman Empire was effectively split into two parts in the 4th century AD - an Eastern Roman Empire, and Western Roman Empire, each with their own Emperor, courts, etc. Theoretically they were both the same entity. In practice, they were separate entities, to the point of warring and attempting to place puppet Emperors on one another. Even while the Empire was being invaded constantly by migrating barbarian tribes.