In the 440s, the Huns began to direclty attack the Roman Empire.
The History of Rome - 169- Huns and Vandals and Goths, Oh My
In the 430s the Romans dealt with increasingly agressive and confident barbarian tribes living both inside and outside the traditional borders of the Empire.
The History of Rome - 168- The Rise of Aetius
In the late 420s AD, the Roman General Flavius Aetius connived and backstabbed his way up the chain of command.