Final answer:
Nobles put down the uprisings in the Peasants' War, and Luther sided with them.
Step-by-step explanation:
In the context of the Peasants' War, the nobles were responsible for putting down the uprisings. Martin Luther, on the other hand, did not support the peasants' cause but rather sided with the nobles. His actions were seen as a rebellion against the Catholic Church, which eventually led to the Protestant Reformation.