Nuns praying at the Saint Joseph Chaldean church. The majority of Iraq's Christians belong to the Chaldean Catholic church. Iraq's Christians are considered one of the longest continuous Christian communities in the world. In 2003 there were an estimated 1.5 million Christians in Iraq. By 2014 Iraqi Christians are thought to number approximately 400,000. Violence, persecution and sectarian strife have forced more than two thirds of the Christian population to flee the country.