Question

unhappy with king johns rule, a group of english nobles
seized power from him
made him give the throne to his brother
forced him to sign the magna carta
started a civil war in england

Explanation:

In 1215, English nobles unhappy with King John's rule forced him to sign the Magna Carta. This document limited the king's power and established certain rights for the nobles. Seizing power directly (without a legal - like document such as the Magna Carta) was not the main outcome. There is no historical record of them making him give the throne to his brother. And while there were tensions, the immediate result was the signing of the Magna Carta rather than starting a full - scale civil war at that very moment.

Answer:

forced him to sign the Magna Carta