Conversation so far:
Who was Muawiyah?
After the peace treaty with Hasan, Mu'awiyah set out with his troops to Kufa.
What was in Kufa?
public surrender ceremony.
Who was surrendering?
Hasan rose and reminded the people that he and Husayn were the only grandsons of Muhammad, and that he had surrendered.

Question: Why did he choose to surrender?
Self-contained rewrite: Why did Hasan Rose choose to surrender?