Answer:
One way to explain the passage, the "conquered...vanquish(ing) their conquerors," was the fact that Central Asian's nomadic people often conquered the civilized places. Their devastating techniques allowed them to defeat their conquerors.
Step-by-step explanation:
Central Asia's climate and geography resulted to "nomads" who were constantly looking for favorable places which they can use for agriculture. In order to to this, they needed to launch several campaigns of conquest to the already established Asian civilizations. This led to a widespread conflict in the area. A great example of this is the "Mongol Conquest" in Eurasia.
So, this explains the answer.