When Eshan Mahmoud and Ghazalah Ghroud got married in their native village of Shirka in April 2014, they paid 150,000 dinar - just over 100 euros - for someone to arrange their marriage documents in the nearby city of Mosul.

But before the requisite papers had been issued, bearded and shaggy haired militants of the so-called Islamic State (IS) swarmed the area, and took control of Shirka. Soon after, the jihadists stormed Mosul and declared a caliphate that was to rule over Iraq's second largest city and its hinterland for over two years.

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In its attempt to create a lasting successor to the government in Baghdad, the terror group established its own bureaucracy to administer the millions of people under its rule. New marriages had to be registered at an IS court, or the couples would not be entitled to the public services that were controlled by the insurgents.

The man they paid to procure their papers had run off with the money, so Ehsan and Ghazalah were not registered as husband and wife. But they were reluctant to submit to the bureaucracy of their new rulers and did not get an IS marriage certificate.

"People told us they were not the official state. Also the courts in Mosul were being hit by airstrikes, it was a dangerous place to go," said Ehsan.

The insurgents never found out that the couple defied their instructions. But the secret became difficult to keep when Ghazalah got pregnant and gave birth to their son. In order to fool the IS administrators, the family came up with an unusual ploy.

"When we got our boy, we declared him to be my father's child, so that my son was registered with them as my brother," said Ehsan.

Mobile courts seek out the displaced

The Iraqi military launched its operation to retake Mosul and the surrounding area in October. Ehsan, now 18, and Ghazalah, 22, fled their village when the fighting drew near earlier this year, and ended up in the Hassansham displacement camp outside Mosul. Here, they finally got their chance to make their marriage official.

Once a week, Iraq's judiciary reaches out to the hundreds of thousands of displaced moored in dusty camps in Kurdish-controlled territory near Mosul in the sweltering summer heat: Every Thursday, a judge and a judicial clerk from Nineveh governorate arrive and set up shop in a container in the midst a sea of tents.

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The judge tours the camps scattered on the plains near Mosul, and Hassansham is the destination this week. There is no shortage of work. According to the International Organization for Migration (IOM), over 800,000 people have been displaced by the battle to retake Mosul, Iraq's second largest city, from IS. Over 600,000 still remain in the camps even now, though the guns were silent in Mosul by mid-July.

Many of these people are in areas that fell to Kurdish forces after IS was expelled. It is near impossible for the displaced to cross the internal border to leave the autonomous Kurdish zone and then return to the camp, so the only way to get hold of new documents is if the courts come to them.

Around 8,000 couples seek to have their marriage registered, says Anam Showani, a lawyer working with Qandil, an NGO that conceived of the idea of the mobile courts and helps organize the visits.

Marriage certificates give access to better rations in the camps. They also allow couples to register their children, even though that next step has to be done in Mosul.

The huge backlog of unregistered marriages is only slowly being worked through. Only 20 to 25 documents are issued each time the mobile court comes to a camp for a few hours, says Anam Showari.

Children left stateless

Jassem Mohammed and Najla Hamed are among the fortunate few.

The couple tied the knot three weeks after Mosul had fallen to the insurgents and IS had come to their native village of Zanazel. Jassem, 21, and Najla, 22, decided to go ahead with the wedding anyway, and spent the first three years of married life in the jihadists' self-proclaimed Islamic State, where the laws and institutions of the Iraqi government were rendered meaningless.

They did not approve of IS, and never registered their marriage with the group. Their principled stand soon proved problematic. Shortly after their marriage, Najla got pregnant, and gave birth to a girl. A year later, a boy was born.

But because they had rejected the insurgents' bureaucracy, Jassem could not take his wife to the hospital to give birth.

"We couldn't go to the hospital because we were not registered as married, so a midwife came and Najla delivered at home," said Jassem.

The young family was also deprived of additional food rations distributed by IS, but Jassam and Najla held firm and bided their time. Iraqi forces finally reached Zanazel the following spring, and the family fled to escape the fighting. They ended up in the sprawling Hassansham Camp.

But camped out in territory claimed by the autonomous Kurdish government, their two children are essentially stateless. Until the couple makes it to a court in Mosul, the kids cannot be registered as Iraqi citizens.

Married at last

Twenty-one-year-old Qassim Hassem and his 26-year-old wife Shama Qassim also registered their marriage with the mobile court in Hassansham.

Qassim and Shama did not resist the insurgents' attempt to recreate a state bureaucracy. When they got married shortly after the terror group took over their village, they registered their union at an IS court.

"We had to do it, otherwise we could not have moved freely," claims Qassim. He has brought the IS wedding certificate with them to support their case in the container courtroom. But the terror group's document does not impress the judge, who instead issues a legal Iraqi certificate after asking the two a few questions while the clerk notes down their details in a thick ledger.

Relieved, Qassim and Shama step out of the container, their wedding legal at last.