Behind him and his people are the Vandals, untold millions of them, waiting for a moment of weakness, ready to destroy us.

7 seconds sound clip from the The Fall of the Roman Empire (1964) movie soundboard.

You can hear this line at 01:56:01.491 in the Blu-ray version of the movie.

Quote context

[...]

- The Roman peace that Marcus Aurelius promised.

- In the name of Caesar... In the name of Caesar!

- Caesar has asked me when has Rome ever been greater or stronger? I say in answer to Caesar: Never has Rome been greater or stronger than now.

- And what is it that has kept our empire together? Our strength! Our might!

- Equality... Freedom... Peace. Who is it that uses these words but Greeks, and Jews, and slaves?

- Behind him and his people are the Vandals, untold millions of them, waiting for a moment of weakness, ready to destroy us.

- If we take these barbarians in amongst us, our enemies will say is it because we are weak. Then they will pour in on us from everywhere.

- It will be the end of the Roman Empire. It will be the end of Rome.

- The end of Rome?

- How does an empire die? Does it collapse in one terrible moment? No. No! But there comes a time when its people no longer believe in it. Then, then does an empire begin to die.

[...]