The Martyrdom of Imam Ali is a significant national holiday in Iran, commemorating the death of Ali ibn Abi Talib, the cousin and son-in-law of the Islamic Prophet Muhammad. Ali is revered not only as a stalwart warrior in Islam, but also a wise theologian, philosopher, and foremost spiritual leader. He was the fourth caliph (successor to Muhammad) of the Islamic community, and Shia Muslims regard him as the first Imam. His martyrdom is a day of mourning for millions of Shias worldwide, with a major concentration in Iran.

This day's observance typically includes religious processions, prayers, and hymn singing. Many people will visit mosques and other religious sites, including Imam Ali’s Shrine in Najaf, Iraq, to pay their respects. Participants often wear black to signify mourning, and in some regions, communal feasts are prepared. Acts of self-flagellation are also common, as believers commemorate Imam Ali's courage and enduring suffering.

The Martyrdom of Imam Ali is an opportunity to reflect upon the teachings and contributions of Imam Ali to Islam. Beyond religious rites, the day is also marked by recitations of poetic eulogies and dramatic re-enactments of the events leading up to Ali's assassination. While the day is marked by solemn reflections, it also serves as a source of unity and community togetherness amid the mourning.