Shia Islam
The year 632 marked the death of Muhammad, the prophet who founded Islam. His cousin and son-in-law Ali ibn Abi Talib stood ready to lead the community. A gathering at Saqifa in Medina changed everything. Abu Bakr, Umar, and other companions elected Abu Bakr as caliph instead of Ali. This meeting created a political split that would define centuries of Islamic history. Shia Muslims believe Ali was meant to be the successor by divine decree. They view the election at Saqifa as an usurpation of his rightful authority. The First Fitna civil war erupted between 656 and 661 CE. It began as revolts against Ali's rule but escalated into full-scale conflict. Battles like the Battle of the Camel and the Battle of Siffin tested the unity of the early Muslim empire. Ali established his capital in Kufa after being invited to become the fourth caliph following Uthman's murder in 657. He faced opposition from Muawiyah, the governor of Damascus. In 661, Ali was assassinated by a Khariji assassin while praying in Kufa. This event solidified the divide between those who supported Ali's lineage and those who followed the Umayyad dynasty.
Muawiyah died in 680 CE and passed the caliphate to his son Yazid. This action broke the peace treaty made with Hasan ibn Ali. Yazid demanded allegiance from Husayn ibn Ali, Ali's younger son. Husayn rejected this request for loyalty. A groundswell of support in Kufa encouraged him to return there and take his position as caliph. He collected his family and followers in Medina and set off for Kufa. An army of Yazid's men blocked them near Karbala. Rather than surrendering, Husayn and his followers chose to fight. Approximately 72 of his family members and followers were killed in the Battle of Karbala. Husayn's head was delivered to Yazid in Damascus. The Shia community regard Husayn ibn Ali as a martyr. They count him as an Imam from the Ahl al-Bayt. The battle is often cited as the definitive separation between the Shia and Sunni sects of Islam. It occurred on the tenth day of Muharram, now commemorated as the Day of Ashura. This event transformed Shia Islam from a political faction into a distinct religious sect with its own rituals and shared collective memory.
Shia Muslims believe that Imams are spiritual and political successors to Muhammad. These human individuals rule over the Muslim community with justice. They keep and interpret divine law and its esoteric meaning. The words and deeds of Muhammad and the Imams serve as a guide for the community. They must be free from error and sin. God chooses them through divine decree. Ali was the first Imam of this line. He was followed by male descendants of Muhammad through his daughter Fatimah. There is always an Imam of the Age who serves as the divinely appointed authority. This belief holds that God would not leave humanity without access to divine guidance. Divine wisdom bestowed upon them esoteric knowledge. Their sufferings were seen as a means of divine grace to their devotees. Although the Imam did not receive divine revelation, he had a close relationship with God. Through this bond, God guides him, and the Imam in turn guides the people. Twelver and Ismaili branches attribute infallibility to the Imams. Zaydi Shias do not attribute infallibility to the Imams but require them to fight against corrupt rulers.
The largest branch of Shia Islam is Twelverism. It follows twelve divinely ordained leaders known as the Twelve Imams. Twelvers are also called Imami or Ja'fari after Ja'far al-Sadiq, the sixth Shia Imam. Significant populations exist in Iran, Iraq, and Azerbaijan. The second major group is Zaydism. Followers recognize Zayd ibn Ali as the fifth Imam. They believe any descendant of Hasan or Husayn could become the next Imam if they meet certain conditions. Zaydis constitute roughly 42 to 47 percent of Yemen's population. The third main branch is Isma'ilism. These followers accept Ismail ibn Jafar as the spiritual successor to Ja'far al-Sadiq. They focus on the deeper esoteric meaning of Islamic faith. The Nizari Ismailis follow Karim al-Husayni Aga Khan IV as their current Imam. Another subgroup includes the Dawudi Bohras led by a Da'i al-Mutlaq. The Druze faith split from mainstream Ismailiism when Al-Hakim bi-Amr Allah disappeared in 1021 CE. They believe he was God incarnate and will return to bring justice.
Several nations arose based on Shia leadership following the Battle of Karbala. The Idrisids ruled in western Maghreb from 788 to 985 CE. The Qarmatians established an Ismaili Iranian dynasty with headquarters in Eastern Arabia and Bahrain starting in 899 CE. Buyids were a Twelver Iranian dynasty that controlled large portions of Iran and Iraq between 934 and 1055 CE. The Fatimid Caliphate emerged in 909 CE under Abu Abdallah al-Shi'i. They controlled much of North Africa, the Levant, parts of Arabia, and holy cities like Mecca and Medina. Cairo was founded by the Fatimid general Jawhar ibn Abdallah. The Safavid Empire dominated Persia from 1501 to 1736. Shah Ismail I proclaimed Twelver Shia Islam as the official religion of Iran in 1501. This caused sectarian tensions across the Middle East. The Ottoman Turks rebuilt Sunni shrines in Iraq after conquering it in 1533. In modern times, the Houthi movement took over Yemen's government in 2014. They are known as Ansar Allah or Partisans of God.
Shia Islam is followed by 10 to 13 percent of all Muslims worldwide. Estimates place their numbers at 200 to 260 million followers as of 2025. Shia Muslims form a majority in Iran, Iraq, and Azerbaijan. About half of Bahrain's citizen population identifies as Shia. Significant communities exist in Lebanon, Kuwait, Turkey, Yemen, Saudi Arabia, Afghanistan, and the Indian subcontinent. Iran stands as the only country where Shia Islam forms the foundation of its laws and governance system. Pew Research Center data from 2009 showed Iran had between 66 and 69.5 million Shias. Pakistan held about 25.3 million Shias. Iraq contained roughly 19 to 24 million Shias. India hosted between 12.3 and 18.5 million Shias. Yemen had approximately 7 to 8 million Shias. Turkey counted between 6 and 9 million Shias. Azerbaijan had around 4.6 to 5.6 million Shias. Afghanistan held about 3 million Shias. Lebanon had roughly 2.1 million Shias making up over 31 percent of its population.
The history of Shia-Sunni relations has often involved religious discrimination and violence. Sunni rulers under the Umayyad dynasty sought to marginalize the Shia minority. Later Abbasids turned on their Shia allies and imprisoned or killed them. In 1514, Ottoman Sultan Selim I ordered the massacre of 40,000 Alevis and Bektashi. He announced that killing one Shia had as much otherworldly reward as killing 70 Christians. Al Saud-Wahhabi armies attacked Karbala in 1802 during the First Saudi State. They sacked the city and destroyed shrines in Najaf. During Saddam Hussein's rule, Shia political activists were arrested, tortured, expelled, or killed after an assassination attempt against Tariq Aziz in 1980. The Islamic State organization persecuted Shias in Northern Iraq alongside genocide of Yazidis. Malaysia declared Shia Islam a deviant sect in March 2011 but allowed private practice. Most Shia sacred places in Saudi Arabia have been destroyed by Al Saud-Wahhabi armies since 1925. A bomb destroyed the shrine of Al-Askari Mosque in Samarra in 2006. Today, Shia Muslims remain a marginalized community in many Sunni-dominant Arab countries.
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Common questions
When did the political split between Shia and Sunni Islam begin after Muhammad's death?
The political split began in 632 when a gathering at Saqifa elected Abu Bakr as caliph instead of Ali ibn Abi Talib. This event created a division that defined centuries of Islamic history.
What happened during the Battle of Karbala on the tenth day of Muharram?
Approximately 72 family members and followers of Husayn ibn Ali were killed by an army loyal to Yazid near Karbala. The battle is cited as the definitive separation between Shia and Sunni sects and occurred on the tenth day of Muharram, now commemorated as the Day of Ashura.
Who are the Twelve Imams followed by Twelver Shia Muslims?
Twelvers follow twelve divinely ordained leaders starting with Ali as the first Imam and continuing through male descendants of Muhammad via his daughter Fatimah. Ja'far al-Sadiq serves as the sixth Imam for this branch known as Imami or Ja'fari.
Which countries have Shia Muslim majorities according to 2025 estimates?
Shia Muslims form a majority population in Iran, Iraq, and Azerbaijan. About half of Bahrain's citizen population also identifies as Shia.
When did Shah Ismail I make Twelver Shia Islam the official religion of Iran?
Shah Ismail I proclaimed Twelver Shia Islam as the official state religion of Iran in 1501. This decision caused sectarian tensions across the Middle East and led to conflicts such as the Ottoman conquest of Iraq in 1533.