Ali was assassinated in 661 by a Kharijite partisan. Six months later in the same year, in the interest of peace, <answer>Hasan ibn Ali</answer>, highly regarded for his wisdom and as a peacemaker, and the Second Imam for the Shias, and the grandson of Muhammad, made a peace treaty with Muawiyah I. In the Hasan-Muawiya treaty, <answer>Hasan ibn Ali</answer> handed over power to Muawiya on the condition that he be just to the people and keep them safe and secure, and after his death he not establish a dynasty. This brought to an end the era of the Rightly Guided Caliphs for the Sunnis, and <answer>Hasan ibn Ali</answer> was also the last Imam for the Shias to be a Caliph. Following this, Mu'awiyah broke the conditions of the agreement and began the Umayyad dynasty, with its capital in Damascus.
Who made peace with Muawiyah I?
Hasan ibn Ali