The Islamic State’s reign of terror, which turned ancient ruins and city squares into theaters of death, was not a random outburst of violence but a meticulously engineered system of psychological warfare designed to shatter entire populations through the public spectacle of execution. From the first filmed beheading of an American contractor in 2004 to the burning of a Jordanian pilot in a cage, the group weaponized modern media to broadcast medieval cruelty, leaving a scar on the global conscience that remains unhealed a decade later.

The genesis of this brutality can be traced to a single man, Abu Musab al-Zarqawi, a Jordanian militant whose vision of jihad was built on the principle that terror must be seen to be effective. In 2004, long before the world knew the name ISIS, Zarqawi was already staging murders in Iraq with a camera rolling, transforming killing from a private act into a public message. His first major production was the execution of Nick Berg, an American civilian contractor, who was forced to state his name before masked men severed his head in a video that spread across the internet like wildfire.

The cold, deliberate staging of Berg’s murder stunned a global audience that had never witnessed such calculated violence outside of a horror film. Zarqawi understood that the shock value of the footage would travel faster than any ground offensive, embedding fear into the psyche of viewers thousands of miles away. That same summer, he personally oversaw the beheading of another American, Eugene Armstrong, repeating the formula to ensure the world understood that this was not an isolated incident but a new standard of warfare.

Zarqawi’s cruelty was indiscriminate, targeting foreigners and locals alike, with anyone outside his narrow interpretation of faith deemed an enemy worthy of death. He openly crucified people in public squares and ordered the execution of Sunnis, Shiites, aid workers, and soldiers, earning the chilling nickname “Sheikh of the Slaughterers.” His methods were a fusion of ancient punishments and modern technology, using beheadings, crucifixions, and burnings to create a climate of absolute submission through terror.

When Zarqawi was killed in a US airstrike in 2006, the violence he had unleashed did not die with him, but instead lay dormant, waiting for the chaos of the Syrian civil war to provide fertile ground for its resurgence. By 2013, a group calling itself the Islamic State of Iraq and Syria, or ISIS, emerged from the shadows, seizing vast swathes of territory with breathtaking speed. By mid-2014, they controlled a third of both Syria and Iraq, declaring a caliphate under the leadership of Abu Bakr al-Baghdadi.

With land came the infrastructure for mass slaughter, and the capture of Mosul, Iraq’s second-largest city, in July 2014 signaled the beginning of a wave of executions on an industrial scale. Captured soldiers and civilians were killed in large numbers, with witnesses later describing dozens of severed heads placed on spikes and bodies dumped into mass graves. These killings were not hidden; they were designed to be seen and remembered, serving as a grim warning to anyone who might consider resistance.

The assault on the Yazidi population in Sinjar was a genocide that unfolded with horrifying efficiency, as thousands of men were executed and dumped into mass graves while women and girls were kidnapped into sexual slavery. The United Nations would later officially recognize these crimes as genocide, but for the victims, the recognition came too late. In Baghdad and other provinces, police officers and soldiers who refused to pledge loyalty to ISIS were executed on the spot, with banners hung across cities warning that disobedience meant death.

Executions became a daily reality under ISIS rule, a tool of governance used to keep the population silent and obedient through sheer terror. A later United Nations report described the campaign as an effort to control civilians through fear, with even the smallest act of defiance resulting in public torture or death. Children were not spared, with some forced to watch executions and others trained to carry them out, appearing in later videos as child soldiers shooting prisoners under direct orders.

The world initially heard only rumors of these atrocities, but ISIS was determined to confirm them by releasing propaganda videos that were carefully staged and deliberately shocking. These films were not amateur recordings but professional productions designed to maximize psychological impact, showcasing the group’s power and brutality to a global audience. The videos served a dual purpose: to terrify enemies and to attract new recruits drawn to the image of strength and ruthlessness.

Foreign journalists and aid workers became prime targets, seen as powerful symbols whose deaths would generate maximum media coverage. James Wright Foley, an American journalist kidnapped in Syria in 2012, became the first American executed by ISIS in a video released on August 19, 2014, showing him kneeling in an orange jumpsuit before being beheaded. The shock of Foley’s murder was compounded just two weeks later when Steven Sotloff, another American journalist, was executed in the same manner.

The pattern was clear: each video followed a similar script, with a hostage in an orange jumpsuit, a masked militant with a knife, and a final speech blaming the victim’s government. British aid workers David Haines and Alan Henning were executed in quick succession, with Henning’s death hitting especially hard as he was a volunteer who had traveled to Syria to help civilians. American aid worker Peter Kassig, who had spent years helping war victims, was also executed, his death announced in the final moments of Henning’s video.

By the end of 2014, ISIS had released a horrifying series of execution videos featuring Americans, Britons, and Japanese hostages, each one more disturbing than the last. The constant exposure to these killings made them feel like a live broadcast of violence, a deliberate campaign to spread fear as far and as fast as possible. For ISIS, the attention was a recruitment tool, attracting individuals who were drawn to the group’s image of power and brutality.

In 2015, ISIS pushed its violence even further, crossing lines that many believed could not be crossed. The capture of Jordanian Air Force pilot Moaz al-Kasasbeh led to one of the most shocking executions ever filmed, as he was locked inside a metal cage and burned alive. The video of Kasasbeh’s death stunned the world, a deliberate demonstration that ISIS was willing to kill in the most painful and extreme ways imaginable.

Just days earlier, Japanese journalist Kenji Goto had been executed, having traveled into Syria to try to rescue a friend who had also been taken hostage. The Japanese public was thrown into mourning as the footage was replayed across television networks. By this point, the pattern was unmistakable: ISIS was using hostage executions as a tool of psychological warfare, sometimes to pressure governments and other times purely for propaganda purposes.

The violence was not limited to Westerners, as Egyptians, Nigerians, Syrians, and many others were executed after being labeled as spies or apostates, often with no evidence and no real trial. In June 2015, a video showed executions carried out using cages, explosives, firearms, and fire, with men accused of spying locked inside metal cages and slowly drowned in a pool of water. Others had explosive devices strapped around their necks and were blown apart, while some were forced into cars that were then set on fire.

ISIS loved to film executions, with soldiers waving phones while cutting throats and posting videos online immediately. A short video of an execution could rack up millions of views, and the cruelty made the group famous. To ISIS, every public killing was a theatrical warning, and they often executed people publicly in conquered towns, holding open trials in stadiums where accused people were led out blindfolded before a crowd.

Judges wearing black turbans and explosives belts ordered executions, with men kneeling, hands tied, before being shot or beheaded.

The international videos targeted governments and the public directly, with ISIS fighters often speaking in flawless English to explain their actions to the camera. Nobody could watch such videos without horror, and each time a hostage’s life was snuffed out, world leaders promised revenge. The West launched an international air campaign partly because of those images, and while ISIS wanted to terrorize, they also united the world against them.

By late 2015, after ISIS began losing territory, their violence against civilians became even more brutal. In and around Mosul, they rounded up Christian minorities, with videos later surfacing showing hundreds of Christian men dressed in orange jumpsuits kneeling in rows before being beheaded. One of the most shocking videos showed 21 Egyptian Coptic Christian laborers who had been kidnapped in Libya, marched onto a beach, forced to kneel, and shown praying quietly before their throats were cut.

Captured soldiers and police officers also faced brutal deaths, with any member of the military who fought ISIS and was captured often executed immediately. Over time, mass graves began to appear across Iraq and Syria, with one example in Hawija containing 260 bodies of police troops who had been shot and chopped up. The group also posted lists online naming people they accused of being spies, and once named, those people were hunted down and usually killed on the spot.

By the time ISIS lost Mosul in 2017 and Raqqa later that same year, the full scale of the damage was impossible to ignore. During just two years of control, public executions and secret killings had destroyed entire communities, with hundreds of thousands of people either fleeing their homes or dead. ISIS was officially labeled a criminal organization responsible for some of the worst war crimes in modern history, but the horror they left behind did not disappear with their defeat.

During the final battles for cities like Mosul and Raqqa, ISIS often executed civilians, captured rebels, or anyone they suspected of betrayal before retreating. When they finally fled, they left behind physical proof of their crimes that could not be erased. In Mosul in 2017, investigators began uncovering mass graves, with one pit alone containing around 500 bodies of mostly Iraqi civilians and former soldiers who had been shot.

Other graves held villagers whose bodies showed signs of decapitation.

In Raqqa, Syria, excavation teams made equally disturbing discoveries, finding wells where ISIS had forced victims inside and then buried them alive. These sites showed that executions were not only public acts of terror but also quiet killings meant to erase people completely. As troops moved through the ruins, they found the tools ISIS had used to carry out executions, including suitcases filled with bomb vests, knives still stained with blood, and metal cages like the ones used in filmed drownings.

In 2018, when the town of Baghouz, the last major ISIS stronghold, was captured, residents showed journalists photographs of fresh graves and bodies found with their hands tied. These were signs of executions carried out by ISIS fighters even in their final days. For families left behind, the end of ISIS control did not bring peace, as many returned to empty homes and destroyed neighborhoods, with survivors describing the beatings and beheadings that happened in public to remind everyone of the consequences of disobedience.

Years later, courts in Europe and Iraq began holding ISIS members accountable, with two militants from the cell nicknamed The Beatles convicted for the murders of hostages including James Foley and Steven Sotloff. In Iraq, many ISIS executioners were put to death for their crimes, but not all were caught. Some leaders were killed in raids and others disappeared, with Abu Bakr al-Baghdadi dying in 2019 after blowing himself up during a raid.

Even with ISIS broken as a military force, the pain has never truly faded, with many families only able to recover fragments of bones instead of full bodies.

The 21 Coptic Christians murdered on the Libyan beach were later honored as saints by their church, but their families continue to live with the memory of how they died. In late 2020 and throughout 2021, trials began for those involved in the beach executions and other massacres, with survivors and witnesses stepping forward to tell what they saw and endured. Today, newspapers and memorials keep the memory alive, with the names of the executed carved into stone as a reminder that they were ordinary people caught in a nightmare.

Even though the ISIS caliphate is gone, the lessons remain, with soldiers and reporters studying those videos to teach the world about the depths of human cruelty. International law fights to bring war criminals to justice, and the group’s story has become a warning about what happens when terror is weaponized and broadcast to the world. ISIS wanted to spread terror, but instead, their story became a testament to the resilience of survivors and the enduring need to remember the horrors they inflicted.