Pope Francis will visit Iraq on a historic four-day trip beginning on March 5 to preach inter-faith coexistence.
Iraq is overwhelmingly Muslim but hosts several ancient Christian communities.
There are 14 officially recognised Christian sects in Iraq. Most live in Baghdad, the northern Nineveh Plains province and Iraq's self-run Kurdistan region.
These are the main Christian communities in Iraq:
- Chaldean (80 per cent)
- Syriac (10 per cent)
- Assyrian (5 per cent)
- Armenians (3 per cent)
- Arabs and smaller groups (2 per cent)
Chaldeans are the most numerous of Iraq's Christians, accounting for up to 80 per cent of the group.
The Chaldean Church is Eastern Rite, affiliated with the Roman Catholic Church but allowed to keep its traditions and rituals.
It was founded in Mesopotamia, what is now modern-day Iraq, in the first century AD.
The church is based in Baghdad and led by Cardinal Louis Raphael Sako. Most Chaldeans live in Iraq, Iran and Lebanon.
They speak a version of Aramaic, a Semitic language spoken at the time of Jesus. There are 110 Chaldean churches across Iraq.
Syriacs make up about 10 per cent of Iraqi Christians. They include Catholics, which are the majority, and Orthodox.
The northern towns of Qaraqosh, Bashiqa and Bartella are home to the biggest Syriac communities in the country.
The main Syriac Catholic church is based in Lebanon while the Orthodox church is based in Syria. There are 82 Syriac churches in Iraq.
Assyrians, including Assyrian Catholics, make up about 5 per cent of Christians in Iraq.
Most are originally from Iran and Turkey. Many of them fled to Iraq after massacres by the Ottoman army during the First World War.
Assyrians refer to the killing of their people in 1915 as a genocide, which took place about the same time as the massacre of Armenians.
There are 21 Assyrian churches in Iraq, 17 of them in Baghdad.
About 3 per cent of Iraqi Christians are Armenian. After the genocide in 1915-1923 by the Ottoman Empire, many of them fled to Iraq.
They speak Armenian. There are 19 Armenian churches in Iraq, Orthodox and Catholic.
Arabs and smaller groups
Arab Christians make up about 2 per cent of the Iraqi Christian population.
There are also three Greek Orthodox and four Coptic Orthodox churches in Baghdad, and 57 Roman Catholic churches across the country, as well as a small number of Protestants.