Religion in Iraq is overwhelmingly Islamic, with roughly 95% of the population identifying as Muslim, making Iraq a Shia-majority country that holds two of Shia Islam's holiest cities, Najaf and Karbala. The remaining few percent belong to ancient minority faiths, including Christians, Yazidis, and Mandaeans, whose roots in this land stretch back thousands of years to the very birthplace of organized religion.
The Religious Makeup of Iraq Today
Iraq is one of only a handful of countries in the world where Shia Muslims form the majority. Although precise figures are difficult to confirm because Iraq has not conducted a full census including religion since the 1980s, the broadly accepted breakdown is as follows:
- Shia Islam: approximately 55–60% of the population, concentrated in the south and parts of Baghdad.
- Sunni Islam: approximately 35–40%, dominant in the north and west, including the Arab Sunni heartland and the Kurdish regions.
- Christianity: around 1%, mostly Chaldean Catholics, Assyrians, and Syriac Christians.
- Yazidism: roughly 1–1.5%, an ancient monotheistic faith centered in northern Iraq.
- Other minorities: a small remainder including Mandaeans, Kaka'i, and a tiny surviving Jewish community.
Most Iraqi Sunnis and Shia alike follow Arab ethnic lines, while the Kurds of the north are predominantly Sunni Muslim but identify strongly by ethnicity rather than sect. This overlap of religion and ethnicity has shaped Iraqi politics profoundly.
A Cradle of World Religions
The land that is now Iraq, ancient Mesopotamia, gave humanity some of its earliest organized faiths. The Sumerians, Babylonians, and Assyrians worshipped a vast pantheon including Marduk, Ishtar, and Enlil, building towering ziggurats as temples to their gods. The ruins of Ur, dated to around 2100 BCE, and the legendary city of Babylon remain on Iraqi soil.
Iraq is also deeply woven into Abrahamic tradition. Jewish tradition places the birthplace of the prophet Abraham at Ur in southern Iraq, and Babylon was the site of the famous Jewish exile. Christianity arrived in the first century, and the Church of the East, once one of the largest Christian bodies in the world, spread from here as far as China. Islam came with the Arab conquest in the 7th century and has defined Iraqi life ever since.
Why Iraq Matters to Shia Islam
Few places carry more weight in Shia Islam than Iraq. The city of Najaf houses the Imam Ali Shrine, the tomb of Ali ibn Abi Talib, cousin and son-in-law of the Prophet Muhammad and the figure from whom Shia Islam takes its name. Nearby Karbala is sacred as the site where Imam Hussein, Ali's son, was martyred at the Battle of Karbala in 680 CE, an event that gave Shia Islam its enduring identity of sacrifice and mourning.
The annual Arbaeen pilgrimage to Karbala is among the largest peaceful human gatherings on Earth, regularly drawing over 20 million participants who walk the roughly 80-kilometre route from Najaf. Along the way, Iraqi volunteers run free food and rest stations called mawakib, a vast act of communal hospitality. Najaf is also home to the Wadi al-Salaam, one of the world's largest cemeteries, where Shia Muslims from across the globe seek burial near Imam Ali.
Ancient Minorities Under Pressure
Iraq's smaller faiths are among the oldest continuously practiced religions anywhere, but they have suffered devastating decline. The Christian population, which numbered well over a million before 2003, has fallen to a small fraction of that after decades of conflict and displacement. The Yazidis, who hold the Peacock Angel (Melek Taus) as central to their belief and revere the Lalish Temple as their holiest site, endured a genocide at the hands of ISIS in 2014 that the United Nations formally recognized as such.
The Mandaeans, followers of an ancient Gnostic faith, regard John the Baptist as their greatest prophet and perform ritual baptisms in flowing river water. Iraq's Jewish community, once one of the oldest and most vibrant in the world, was almost entirely displaced after 1948 and now numbers only a handful of individuals. To explore more about the nation that holds this remarkable spiritual heritage, see our iraq country guide.
Religious Life and Observance
Religious practice is woven into daily Iraqi life. The most intense observance is Ashura, which commemorates Hussein's martyrdom with solemn mourning processions and theatrical reenactments of the Battle of Karbala. Sunni and Shia Muslims alike mark the two Eid festivals and Friday congregational prayers. Iraq's remaining Christians continue to celebrate Christmas and Easter in their historic communities around Mosul and the Nineveh Plains, where monasteries such as Saint Matthew's count among the oldest in the world. The Yazidis observe distinctive festivals like the Feast of Jemaya, maintaining customs found nowhere else.
Frequently Asked Questions
What is the main religion in Iraq?
Islam is the main religion in Iraq, practiced by roughly 95% of the population. Iraq is a Shia-majority country, though it also has a large Sunni minority, with the two groups together accounting for nearly the entire population.
Is Iraq a Sunni or Shia country?
Iraq is a Shia-majority country, with Shia Muslims making up around 55–60% of the population. Sunni Muslims form a significant minority of roughly 35–40%, dominant in the north and west of the country.
What are the holiest religious sites in Iraq?
The holiest sites include the Imam Ali Shrine in Najaf and the Imam Hussein Shrine in Karbala, both central to Shia Islam. The Lalish Temple in the north is the holiest site of the Yazidi faith.
Are there Christians in Iraq?
Yes, Iraq has an ancient Christian community dating to the first century, including Chaldean, Assyrian, and Syriac Christians. Their numbers have declined sharply since 2003 but they remain an important part of Iraq's religious mosaic.