In this special episode of Head On History we discuss the history, origin, and practices of Muharram and Ashura. We start with the Battle of Karbala and the lead up to the schism in the nascent Muslim community. We talk about the martyrdom of Husayn ibn Ali and the consequences for the community. We then explore how mourning and commemorating the tragedy emerged as a practice from the Buyids to the Safavids. We examine how Muharram and Ashura become pivotal in shaping communal identity. We discuss some of the major practices like pilgrimages and Taziyeh plays and the way in which Muahharm and Ashura historically was a point of commonality between Shia and Sunni groups, but how that history has been forgotten.