B. Geographically it overlapped both empires
Answer:
The brilliance of Erwin Rommel 'The desert fox'
and the new tanks from the German Empire (Tiger I, The panther, etc.)
Or you can use the desert. Sand... It got everywhere. Equipment would fail because of that. (Anakin skywalker does not approve. And May the 4th be with you.)
Charlemagne restored him and protected him from being driven out again
hope this helps