[indcons]

That's a great question....I don't know the answer though. If the historical assumptions about the Huns and the Mongols are correct, I guess weather (and the lack of grazing land)must have played a major role in their drive toward Europe.

Most interestingly, I am not aware of the historical record of the Huns after they left Rome following the death of Attila.

[patton]

There was a history channel special on weather and war - all sorts of interesting connections between cold winters (over many years) and invasions heading south.

War for resources, again.

[colorado tanker]

After the wars, the Huns settled the plains of what became Hungary.