A picture of Iran's Ayatollah Ali Khamenei stands in a traffic circle in the northern Iraqi town of Bartella. It is a prominent symbol of Shia Islam in a town that has been historically inhabited by Syriac Catholic and Orthodox Christians. In recent years, the population of Shabak people - a heterodox minority who predominantly identify as Shia Muslims - has increased significantly in the town.

Similarly, in nearby Qaraqosh, flags commemorating Imam Hussein - who is revered by Shia Muslims - fly over the houses around the base of the Nineveh Plain Protection Units (NPU), a Christian paramilitary group.

Demographic changes in the town, which are perceived by some as forced, have led to frustration for many of the area's Christians and others.

"The problem is Sunnis have the Gulf, Shias have Iran, and the Christians have no one," John Hadaya, head of the Syriac Party, told Middle East Eye.

The Shabak presence in Bartella, Qaraqosh and other historically Christian towns significantly increased in the aftermath of the war with the Islamic State (IS) group, when expelled populations returned to their lands or moved from destroyed villages to larger towns.

Nineveh Plains residents disagree on whether demographic change occurring in the area is forced or not. The issue has pitted people who suffered at the hands of IS against each other. It has also highlighted disagreements over Iran and its militia allies' influence in Iraq.

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One Shabak activist spoke to MEE on condition of anonymity out of a fear of pro-Iran militias in the area. He said that Shabak left villages for towns due to poor living conditions in the former.

"The villages have no water, no schools," the activist told MEE. "Where could we live? We needed to be in city centres."

'A result, not a plan'

Both Bartella and Qaraqosh lie in the Nineveh Plains. The area is strategic for the powers in the Middle East. For Iran, it is a connecting area between Shia majority parts of Iraq and Iran's allies in Syria and Lebanon - plus the Mediterranean Sea.

The arable plains are also one of Iraq's official disputed territories claimed by both the autonomous Kurdistan Regional Government (KRG) and the federal Iraqi government. IS controlled much of the Nineveh Plains between 2014 and 2017.

The Nineveh Plains showcase an incredible amount of religious and ethnic diversity. The area north of Mosul includes Kurdish, Turkmen, Arab and Yazidi communities, as well as Christian and Shabak.

During the reign of Iraq's President Saddam Hussein, Iraqi authorities forcibly expelled Nineveh Plains residents from their homes and moved Arabs from elsewhere in Iraq there in an "Arabisation" campaign. This also resulted in homes being sold to Arabs from other parts of the country.

Shabak people were among those made to leave their homes. The Iraqi government's perception that they were Kurds resulted in harsh home destructions and expulsions of Shabak, according to the Iraqi website Niqash.

Saddam persecuted Kurds in Iraq during and following the Iran-Iraq war in the 1980s. After the US invasion in 2003 that toppled Saddam, Islamic militant groups also attacked Shabak communities in Mosul.

The Hashd al-Shaabi or Popular Mobilisation Forces (PMF) - mostly, but not exclusively, Shia militias formed in 2014 to fight IS - played a crucial role in defeating IS, including in areas like the Nineveh Plains that are outside the Shia-majority parts of Iraq. Many PMF groups receive financial, military and political support from Iran.

The PMF presence is clear in Nineveh. The official checkpoint leading to the province from the KRG includes numerous PMF and Imam Hussein flags, as does the road to Bartella.

Graffiti with Shia religious expressions are visible on many of the numerous PMF checkpoints throughout the area. The PMF honours their soldiers who died fighting IS with posters of them carrying the word "martyr" lining the roads.

In the Nineveh Plains, Brigade 30 is one of the main PMF groups and its soldiers are mostly Shabak. Before the IS conflict, the Shabak community had no such military clout.

"After the liberation, Shabak had militias," the Shabak activist said.

Thousands of Christians fled the Nineveh Plains in advance of IS. Others were enslaved or killed. This prompted heavy emigration of Iraq's Christians from the country. The flight of Christians enabled Shabak to move to historically Christian towns, according to the activist.

"Many Christians left Iraq, so areas became Shabak and pictures of Imam Hussein appeared," he said.

The activist said this was not a plan, but a desire to live in areas with better conditions. He blamed the government for the situation.

"It was a result, not a plan. We just wanted water, services, schools for the children," he said. "If the government had given us land, we would've never left our areas."

Even since the areas were liberated from IS control, the Christian population has not returned in the same numbers. This is due to the destruction of homes and the lack of basic services, making the areas almost uninhabitable, while others found work in other regions.

Some Christian leaders in the area also note emigration as a reason the local Christian population has decreased.

"Christians left Iraq, and they accepted this because they had no sources from which to live," Isam Daaboul, the mayor of Hamdaniya, which includes Qaraqosh, told Middle East Eye.

The large size of Shabak families and their practice of polygamy is another contributing factor to their population increase in the Nineveh Plains vis-a-vis Christians.

'Big efforts to change the demographics'

Many Christians from the area believe forced demographic change is taking place. In March, Christian news website ankawa.com published an article on the issue, using the provocative title "Daesh [IS] left and the Shabak came. And dread is there. Why are Christians afraid to return to their homes?".

The article acknowledged Shabak suffering at the hand of IS as well, but accused members of the Shabak community of preventing Christians from coming back to the Nineveh Plains.

"Christians are afraid of returning because of the threat posed by the 'Shabak,'" the article read.

Some Christian politicians use similar language to refer to the situation. Hadaya said that Iran was backing elements of the Shabak community to alter the population makeup of the Nineveh Plains.

"There are big efforts to change the demographics from the residents and the government," he told MEE.

"Shabak people have control and they are close to Iran."

When Iraqis want to change homes, they must obtain papers from local authorities before they can do so legally. This is one way that people affiliated with pro-Iran entities can allegedly receive preferential treatment, thus enabling demographic change.

Christians are fleeing due to security concerns and this apparent power imbalance, and their community's numbers will dwindle if nothing changes, according to Hadaya.

"We have a war against time because emigration is occurring in a non-natural way," he said.

Some advocacy groups for Iraq's Christians also share a concern over demographic change. The US-based Assyrian Policy Institute published a report last year on Christian concerns that proposed new residential settlements would seize their farm lands in Hamdaniya. The proposed areas were under the control of Brigade 30, according to the institute.

Outgoing Iraqi Prime Minister Adel Abdul-Mahdi unsuccessfully tried to remove Brigade 30 from the Nineveh Plains last year, but their supporters protested against this.

Some in the Shabak community share the concerns about the PMF presence in the area, as well. Dozens of Shabak from the Nineveh Plains protested outside the United Nations (UN) compound in Erbil in January against the PMF presence in their native Nineveh.

Not all Christians believe the rumours that Shabak are taking their properties, though. In a small alley tucked away off Bartella's main road, Sliwa Elias and friends sit outside and talk.

"This isn't happening at all," Elias told MEE. "Christians and Shabak live normal lives as neighbours."

Another member of the group, John al-Sabagh, said that Shabak moving into Christian homes happens for economic reasons because of Christian emigration from the area.

"Our problem is we need money and to sell our houses. Sometimes, other Christians can't buy them," he told MEE.

"The guy who buys them is a Shabak Muslim. If it's being supported by anyone, it's Iran."

'Many empty houses'

Many Shabak and other Shia in Bartella deny anyone in their community is taking houses, including those houses abandoned by Christians who fled IS.

"We are not interested in taking Christian people's homes," Hadi Elias told MEE from his shop in Bartella. "There are many empty houses we don't want to take."

Marwa Hussein is a Shabak activist, also from Bartella. She adamantly denied anyone taking homes in an inappropriate way.

"Christian houses being taken by the Hashd, other militias, or other components is a falsehood," she told MEE. Some Iraqis refer to ethnic and religious communities as "components".

Hussein also attributed the decrease in Christian households to emigration.

"On the contrary, there are Christian families who sell their houses to go to Europe."

Iyad Abbas, a Shabak merchant in Bartella, said communal relations were good in the town.

"We are all brothers," he told MEE.

Qusay Abbas, a Shabak member of the Iraqi parliament from the Nineveh Plains, said he did not think his community had any major problems with local Christians.

"There are no problems between Shabak, Christians and others," he told MEE.

Andy Sarhat contributed Aramaic translation and fixing to this report.