Iranians in cities, towns, and villages across the country are marking the day on Thursday by going to mosques or pouring into the streets and joining processions, beating their chests to eulogies, beating the back of their shoulders with light chains, etc.
Iranian people also traditionally cook and distribute charity food among their neighbors, family members, and the poor.
In 680 AD, Imam Hossein (PBUH) and 72 of his companions were martyred in the battle of Karbala in Iraq by the forces of the tyrant ruler of the time, Yazid, the second Umayyad caliph.
Tasu’a is most prominently known for the martyrdom of Imam Hossain’s half-brother, Abolfazl al-Abbas, who fought alongside the imam against the army of Yazid. Abolfazl is highly revered among Muslims as a symbol of loyalty.
The mourning ceremonies reach their peak on the 10th day of Muharram, or Ashura, when Imam Hossein (PBUH) himself was also martyred.