The history: Ashura falls on the tenth day of the Islamic month of Muharram. It is the culmination of the mourning period commemorating the death of Hussein, who Shiites revere as the third Imam. The story of Hussein relates back to the struggle for supremacy within the Muslim community following the death of the Prophet Mohammed, a major event marking the split between the Sunni and Shiite sects. Imam Hussein was the grandson of Mohammed and the son of Ali, a caliph following Mohammed's death.
The pilgrimage: Yazid's forces slaughtered Hussein, along with his relatives and supporters. Hussein's body was buried in the city of Karbala. While subsequent Umayyad caliphs would prevent the construction of a shrine to commemorate his burial, future rulers would eventually build a mosque over his gravesite. It is now one of the holiest sites for Shiites, and the annual destination of millions of pilgrims. Above, Shiites gather outside the Imam Hussein Mosque in Karbala, Iraq, on the day of Ashura.
The schism: The death of Hussein brought an end to the question of succession in the Muslim leadership: Power would now pass down through the hereditary dynasty of the Ummayads, rather than through the family of Mohammed. However, it created an irrevocable split between Sunnis and Shiites that continues to this day, as the two sects swore allegiance to different leaders. Above, Turkish Shiite women take part in a mourning ceremony in Istanbul. Their headscarves carry the name of Zeynep, the sister of Hussein, who is seen by many Shiite women as a role model for her courage and perseverance after being captured by Yazid following the Battle of Karbala.
: To express their anguish at Hussein's martyrdom, many Shiite men flay their skin with chains and knives on Ashura. Above, an Afghan Shiite man beats himself outside the Shiite mosque in Kabul to mourn the death of Hussein.
: Shiite men often draw their own blood by cutting their scalp with the flat end of a sword or knife. In this picture, a procession of Shiite mourners walks through the streets of the Baghdad neighborhood of Sadr City on Dec. 26.
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Rite of passage: Often, Shiite boys will begin the ritual of self-flagellation while still quite young. In the southern Lebanese city of Nabatiyeh, a boy makes the ceremonial cut on his forehead to mark Hussein's death.
: Ashura ceremonies are not unique to the Middle East. An Indian Shiite flays himself with a knife on Dec. 28 in the city of Mumbai.
: The ceremonies of Ashura are about more than ritualistic self-flagellation -- they are an opportunity for Shiites to remember a defining moment in their faith. In Tehran, spectators watch a re-enactment of the Battle of Karbala. The man in red is playing a soldier of Yazid's army, while the fallen Iranian at his feet represents one of Hussein's followers.
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: Ashura is not just a day in which Shiites remember a past political defeat, but also to show their strength in modern political conflicts. In southern Lebanon, Hezbollah organized a massive rally to mark Ashura -- which also served as a show of popular support meant to intimidate Lebanese parties that might seek to challenge their political agenda. Hezbollah Secretary General Hassan Nasrallah used his Ashura address to warn other Lebanese parties against "foreign allegiances" and to blast the Egyptian government for constructing a wall along its border with Gaza, meant to prevent smuggling.
: Hezbollah isn't the only group that used Ashura as an opportunity to advance its political goals. For Iranian reformists, the day was useful because of its religious message -- mourning the use of violence and tyranny to suppress a righteous political cause -- and because the regime-sanctioned demonstrations gave them an opportunity to take to the streets.
As thousands of protesters poured into the street, the pro-government Iranian paramilitary force known as the Basij escalated its use of force in an attempt to maintain order. Police officers fired into the crowds, allegedly killing at least 10 protesters -- including Ali Moussavi, the nephew of former presidential candidate Mir Hossein Moussavi. The Iranian regime also arrested up to 1,500 reformers for their role in the protests, including former Foreign Minister Ibrahim Yazidi, human rights activist Emad Baghi, and several top aides to Moussavi.
: Pro-reformist Iranians were quick to make the connection between the events commemorated by Ashura and their own persecution.
