Muharram rituals in Khorramabad

Shia Muslims believe that Imams are to succeed the reign of the Prophet Muhammad, while Sunnis reject Ali’s claim to be the true successor; therefore, the oppressive rule of Umayyad caliphs prevailed, and Imams were compelled to swear allegiance to the Umayyad caliphs one after another. However, Imam Husayn refused to pledge allegiance to Yazid; thus, the battle of Karbala occurred in 680 AD in the plains of the Iraqi city of Karbala.