The U.S. government estimates the total population at 38.9 million (midyear 2019 estimate). According to 2010 government statistics, the most recent available, 97 percent of the population is Muslim. Shia Muslims, predominantly Arabs but also including Turkoman, Faili (Shia) Kurds, and others, constitute 55 to 60 percent of the population. Sunni Muslims are approximately 40 percent of the population, of which Arabs constitute 24 percent, Kurds 15 percent, and Turkomans the remaining 1 percent. Shia, although predominantly located in the south and east, are the majority in Baghdad and have communities in most parts of the country. Sunnis form the majority in the west, center, and north of the country.

Christian leaders estimate there are fewer than 250,000 Christians remaining in the country, with the largest population – at least 200,000 – living in the Ninewa Plain and the IKR in the north of the country. According to Christian leaders, the Christian population has declined over the past 17 years from a pre-2002 population estimate of between 800,000 and 1.4 million persons. Approximately 67 percent of Christians are Chaldean Catholics (an eastern rite of the Roman Catholic Church), and nearly 20 percent are members of the Assyrian Church of the East. The remainder are Syriac Orthodox, Syriac Catholic, Armenian Catholic, Armenian Apostolic, and Anglican and other Protestants. There are approximately 2,000 registered members of evangelical Christian churches in the IKR, while an unknown number, mostly converts from Islam, practice the religion secretly.

Yezidi leaders continue to report that most of the 400,000 to 500,000 Yezidis in the country reside in the north, and approximately 360,000 remain displaced. Estimates of the size of the Sabean-Mandean community vary. According to Sabean-Mandean leaders, 10,000 remain in the country, mainly in the south, with between 750 and 1,000 in the IKR and Baghdad. Baha’i leaders report fewer than 2,000 members, spread throughout the country in small groups, including approximately 500 in the IKR. The Shabak number between 350,000 and 400,000, three-fourths of whom are Shia. Most Sunni Shabak and some Shia Shabak reside in Ninewa. Armenian leaders report a population of approximately 7,000 Armenian Christians. According to Kaka’i (known as Yarsani or Ahl al-Haq in Iran) activists, their distinct ethnic and religious community has approximately 120,000 to 150,000 members and has long been located in the Ninewa Plain and in villages southeast of Kirkuk, as well as in Diyala and Erbil.

There are fewer than six adult members in the Baghdad Jewish community, according to a local Jewish community leader. In the IKR, there are 70 to 80 Jewish families, according to the Jewish representative in the KRG Ministry of Endowment and Religious Affairs (MERA). There are possibly more, as some Jewish families do not openly acknowledge their religion for fear of persecution, according to the KRG MERA, and NGO sources. According to the KRG Ministry of Endowment and Religious Affairs, there are approximately 60 Zoroastrian families in the IKR.

According to the International Organization for Migration, as of December, nearly 1.5 million persons remain displaced within the country, predominantly in Erbil, Dohuk, and Ninewa Provinces, compared with 1.8 million persons at the end of 2018. Population movements are multidirectional, with some persons fleeing their homes and others returning home. According to the KRG’s Joint Crisis Coordination Center in the KRG, 40 percent of internally displaced persons (IDPs) are Sunni Arabs, 30 percent Yezidis, 13 percent Kurd (of several religious affiliations), and 7 percent Christians. Other religious minorities comprise the remaining 10 percent.