It followed the death of the first Umayyad caliph Mu'awiya I in 680 and lasted for about twelve years .

After the assassination of the third caliph Uthman , the Islamic community experienced its first civil war over the question of leadership , with the main contenders being Ali and Mu'awiya .

Following the assassination of Ali in 661 and the abdication of his successor Hasan the same year , Mu'awiya became Becoming the sole ruler of the caliphate .

Mu'awiya 's unprecedented move to nominate Choosing his son , Yazid , as his heir sparked Causation opposition and tensions soared after Mu'awiya 's death .

Mu'awiya 's unprecedented move to nominate Choosing his son , Yazid , as his heir sparked Causation opposition and tensions soared after Mu'awiya 's death .