Wahida Yaqo, a Christian in the Kurdistan parliament, has prepared a message to the Pope warning of the sharp decline in the number of Christians of Iraq.
Only 100,000 are left in Iraq, Yaqo told Rudaw on Saturday.
Insecurity and instability has dominated Iraq over the past three decades. The last census in Iraq was in 1987, when 1.5 million Christians were counted.
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Iraq's major Christian communities historically have lived in Baghdad, Mosul, the Nineveh Plains, and the Kurdistan Region.
Rudaw's correspondent in the Iraqi capital, Bahman Hasan, reported this summer there are 74 churches in Baghdad, but most have been closed.
"Baghdad was an important and historical city for the Christians. But ISIS and Hashd al-Shaabi emerged, the situation of the Christians deteriorated... There is only one church in Baghdad the Christians are using to pray," Yaqo claimed.
Across the country, he said some 60 churches have been blown up and 12 others shuttered due to the mass emigration of Iraqi Christians since 2003.
During the sectarian conflict after the US-led invasion from 2003 to 2010, at least 810,000 people from other parts of Iraq came to the "safe haven" of the Kurdistan Region, according to KRG statistics.
Of those internally displaced persons (IDPs), 25 percent (202,500) were Christian, Hoshang Mohammed, the director general of the KRG Joint Crisis Coordination Center told Rudaw English.
"Following the re-establishment of relative security, the majority returned to their places of origin," said Mohammed of the period immediately after 2010.
Then about 22,000 Christians remained in the Kurdistan Region, stated Mohammed.
As ISIS extremists moved into Iraq and kidnapped, raped, and murdered the Yezidis in August 2014, word spread quickly to the Christians in nearby Nineveh.
The 2014 wave of Christian displacement followed. According to the KRG, 150,500 Christians registered with the regional government -- again seeking shelter in the Kurdistan Region where they stayed in camps or with the host community.
Assyrian, Chaldean, Syriac and Armenian sects comprise the main Christian community in Iraq.
The pan-Christian non-governmental organization Shlomoo, which painstakingly documented the 2014 displacement, has told Rudaw English about 400,000 Christians were estimated to live in Iraq and the Kurdistan Region before ISIS. Through the ISIS war, about 200,000 went to the Kurdistan Region with about that many fleeing the country.
Many of the Christians who were sheltering in the Kurdistan Region returned to their homes in the Nineveh Plains as Kurdish Peshmerga and Iraqi Security Forces ousted ISIS, "but most have emigrated," Vian Markaus, the office manager for the Independent Commission of Human Rights in the Kurdistan parliament told Rudaw English on Sunday.
"We know of 600 families from Mosul [Nineveh province] currently living in Ainkawa who are still displaced," Nawzad Hakim of Shlomoo told Rudaw English on Sunday, referring to the Christian suburb of Erbil.
The Government of Iraq declared a victory over ISIS in early December. However, stability in the Nineveh Plains fully has not returned following clashes between Kurdish Peshmerga and Iraqi forces supported by Iran-backed, Shiite Hashd al-Shaabi paramilitaries.
"After October, yes, 850 families (5,100 individuals) fled Nineveh Plain," said Mohammed with the KRG.
The diverse disputed or Kurdistani areas including parts of Nineveh are claimed by both Baghdad and Erbil.
"The situation of the Christians in Mosul and Nineveh Plains is worse than all of those in Iraq and Kurdistan. In addition to destroying all the historical and religious places by ISIS, their areas have been controlled by the Hashd al-Shaabi. It has been two years since ISIS left Tel Kayf, Hamdaniya, Qaraqosh. But its people cannot [fully] return," said Yaqo, the Christian MP.
Some Christians have taken up arms and formed their own brigades, others seek the support of the Iraqi government or provincial forces, others have joined Hashd al-Shaabi, and others have joined the Zeravani force of the Peshmerga.
"The threats were there even before ISIS came from Islamic parties. Since ISIS has gone, Hashd al-Shaabi is a threat to Christians in the Nineveh Plains," said Hakim. "They are not willing to return because of threats to their lives. Some of them have been kidnapped or killed."
Because of Nineveh's diversity, internal conflicts also exist, especially between the Christian and Shabak communities over displacement and land ownership.
"The use of Hashd al-Shaabi has changed the demography of the region, especially through the establishment of their brigades through the Shabaks who now receive aid from Iran through Hashd," claimed Hakim, pointing towards Bartella, a town with Shabaks and Christians.
Local and international NGOs have tried to fill the gaps as Christians remain displaced and Baghdad formulates a plan to rebuild the war-ravaged country.
While many of the NGOs remain based in the Kurdistan Region because of its relative safety for Westerners "it has affected the performance and ability of the [international NGOs] to operate here," said Hakim, referring the Iraq-imposed international flight ban at Sulaimani and Erbil airports following punitive measures imposed after the Kurdistan Region's independence referendum in September.
"The NGOs associated with UN agencies like UNHCR or UNDP have remained, but the other NGOs delivering assistance to the NGOs have left," added Markaus.
While some Christians have called for their own autonomous region in Iraq, Hakim said: "We just appeal for our rights and ask especially the US to hear us."
US President Donald Trump's has espoused opposition to Iran, while also allowing the Iran-backed militias to move into areas they historically haven't controlled. Trump did speak with Pope Francis about Iraq's Christians during a Vatican visit in May. His vice president, Mike Pence, has prioritized State Department funding for Iraq and Syria's religious minorities, namely Christians and Yezidis.
"Our message to the West, to the United States is that the Hashd al-Shaabi are a big threat to the Christian areas," added Hakim. "We have historic relations here with Kurdistan with Yezidis and Muslims. But the advent of the Hashd al-Shaabi has destabilized the situation."