Every year, Shiite Muslims ritually lacerate their flesh with blades in honor of Ali and his two sons, Hassan and Hussein. Many people believe that this ritually has its roots in Islam. But the reality is that its rooted in pre-Islamic Iran:
CORRECTION: I said that the Buyids were descendants from Iranians in Central Asia. This was a mistake. Nonetheless, this does not change the fact that Ashura was popularized by Iranians (the Buyids) in Iraq and that Iranians in Central Asia were committing ritual self-mutilation in pre-Islamic times.