Islamic State in Iraq and Syria
- Arabic:
- al-Dawlah al-Islāmiyyah fī al-ʿIrāq wa al-Shām
- Arabic acronym:
- Dāʿish or Daesh
- Also called:
- Islamic State in Iraq and the Levant (ISIL) and
- Since June 2014,:
- the Islamic State
- Date:
- April 2013 - present
- Areas Of Involvement:
- Islam
- sharia
- terrorism
- extremism
- suicide bombing
- Related People:
- Abu Bakr al-Baghdadi
News •
Islamic State in Iraq and Syria (ISIS), transnational jihad movement that has orchestrated or inspired numerous terrorist attacks around the world, including the Paris attacks of 2015, the Brussels bombings of 2016, the Orlando shooting of 2016, and the New Orleans attack of 2025. The organization grew out of an insurgency by Sunni Iraqis, who had been politically dominant under the rule of Saddam Hussein but had been repressed under the political system that replaced him. Formerly an affiliate of al-Qaeda, a militant organization that became notorious for carrying out the September 11 attacks, ISIS began acting autonomously in 2013 and was disavowed by al-Qaeda in early 2014. In June 2014, after making significant territorial gains in Iraq, the group proclaimed the establishment of a caliphate led by the leader of ISIS, Abu Bakr al-Baghdadi. International efforts to defeat the group led to its decline, and both the Iraqi and Syrian governments considered ISIS effectively defeated by November 2017, though ISIS remained active well after its defeat and began seeing a resurgence in Syria in 2024. Certain affiliates, most notably Islamic State–Khorasan Province (ISKP; also called ISIS-K) in Afghanistan, are sometimes referred to as “ISIS,” despite having a leadership base outside of Iraq and Syria.
Roots in Iraq
ISIS has its origins in the Iraq War of 2003–11. Al-Qaeda in Iraq (AQI), its direct precursor, was one of the central actors in a larger Sunni insurgency against the Iraqi government and foreign occupying forces. Under the leadership of Abu Musab al-Zarqawi, AQI was responsible for some of the most spectacular and brutal attacks of that conflict. Shortly after Zarqawi’s death in 2006, the group combined with several smaller militant groups and rebranded itself as the Islamic State of Iraq (ISI), a change that reflected the group’s efforts to expand its appeal as well as its ambition to obtain universal leadership of the country’s Islamic militants. The group’s activities were greatly diminished when many of the Sunni tribes of western Iraq turned against it, however, beginning in 2007. The reasons for that reversal included the ISI fighters’ harsh treatment of the populace in areas under their control and a new counterinsurgency strategy that paid Sunni tribal leaders not to participate in attacks. AQI/ISI was also weakened by the loss of several of its senior leaders in attacks by U.S. and Iraqi forces. In 2010 leadership of the group was taken over by Abu Bakr al-Baghdadi (birth name: Ibrāhīm ʿAwwād Ibrāhīm ʿAlī al-Badrī al-Sāmarrāʾī), who was able to elude U.S. and Iraqi forces until 2019.
The strongly sectarian cast of Iraqi politics at the time, and specifically the repression of Sunnis carried out by the administration of Prime Minister Nouri al-Maliki under the guise of fighting al-Qaeda and remnants of the Baʿath regime, ensured that the Sunni areas of western Iraq remained fertile ground for extremism. The sharpening of Sunni discontent, coupled with the gradual withdrawal of foreign troops, allowed AQI/ISI to make a recovery beginning about 2011, and bombings by Sunni militants once again became a frequent occurrence.
The Syrian theater
The Syrian Civil War, which began as an uprising against the regime of Pres. Bashar al-Assad in early 2011, provided new opportunities for AQI/ISI, whose fighters could easily cross from Iraq into eastern Syria. By late 2012 the assortment of mostly secular rebel groups that had been the mainstay of the armed opposition appeared to be weakening as a result of infighting and exhaustion, and Islamist forces took on a more prominent role. Those included the Islamic Front, an alliance of local Islamist rebel groups; the Nusrah Front, a network aligned with the central faction of al-Qaeda led by Ayman al-Zawahiri; and fighters loyal to Abu Bakr al-Baghdadi. In April 2013 Baghdadi announced his intention to combine his forces in Iraq and Syria with the Nusrah Front under the name Islamic State in Iraq and Al-Shām (ISIS; Shām, a term referring roughly to the Levant, is often translated as “Syria”). The merger was rejected by the Nusrah Front; the split put the two groups in competition, especially for recruits, and eventually resulted in open fighting. (The Nusrah Front later became the leading faction of Hayat Tahrir al-Sham, which in 2024 toppled the Syrian government of Bashar al-Assad.)
ISIS quickly established a zone of exclusive authority in eastern areas of the country that had long ago slipped out of the government’s control. In that zone, which centered on the eastern city of Al-Raqqah, it imposed a strict version of Islamic law. The group’s propaganda, which emphasized its successes in battle and its brutal treatment of enemies and those it deemed to be violators of Islamic law, was thought to have attracted significant numbers of radicalized recruits from outside Iraq and Syria, although the precise numbers remained uncertain. ISIS also seized critical pieces of infrastructure in eastern Syria, such as oil refineries that enabled it to raise revenue by selling oil on the black market.
Expansion and declaration of a caliphate
From its stronghold in Al-Raqqah, ISIS expanded outward, launching successful offensives in both Syria and Iraq. After Iraqi government forces attempted to suppress protests in the predominantly Sunni cities of Fallujah and Al-Ramādī, ISIS joined local militias in fighting back and took control of those cities in January 2014. The capture proved a propaganda boon for ISIS, which flaunted its “liberation” of those cities to aggrieved Sunnis across western Iraq. ISIS fighters then pushed north, shocking government troops and taking Mosul—Iraq’s second largest city—without resistance in June. As ISIS advanced, it used social media to disseminate videos and images that appeared to show ISIS gunmen executing large numbers of captured Iraqi soldiers.
In late June the group released an audio message declaring a caliphate in the territory controlled by ISIS, with Baghdadi as the caliph. In accordance with that declaration, the group began referring to itself simply as “the Islamic State.” The group’s claims to universal leadership of the Muslim community were widely rejected by other Muslim groups.
ISIS began to assume some governmental functions in the areas under its control, such as collecting taxes and organizing basic services. Policing, education, and health care were carried out in accordance with its hard-line interpretation of Islamic law. Yet witness accounts and the group’s own propaganda indicated that ISIS continued to rely on extreme violence against civilians to enforce its edicts and to ensure the compliance of the populace: public executions, amputations, and lashings were routine, and the corpses of the executed were often displayed to the public as a warning against disobedience. There were also widespread reports of sexual violence carried out by ISIS, including forced marriages and sex slavery.
ISIS’s quick advances in Iraq alarmed the international community and set off a political crisis in Baghdad that ultimately led to the toppling of Maliki. Calls for international intervention increased, and on August 8 the United States launched air strikes in Iraq to prevent ISIS from advancing into the autonomous Kurdish region of Iraq. The strikes did halt ISIS’s advance but did not dislodge it from territory in Iraq where it had become entrenched.
ISIS continued to produce gruesome and provocative propaganda. A series of videos in August and September showed ISIS fighters beheading Western journalists and an aid worker in retaliation for the U.S. air strikes. Those images deepened fears that ISIS posed a global threat. ISIS demanded ransom payments and other concessions from foreign governments in exchange for the return of hostages, and it executed the hostages if the governments refused. Most of the hostages were journalists and aid workers, but in late December 2014 the group captured a Jordanian pilot after his fighter jet crashed during a mission against ISIS in Syria. News of the pilot’s capture met with consternation in Jordan, where a large proportion of the public had opposed the country’s participation in the anti-ISIS coalition. Support for military action surged in February 2015, however, after an ISIS video showed the pilot being burned to death by his captors.
Furthermore, once ISIS took control of territory in Iraq and Syria, it engaged in a campaign of cultural cleansing, destroying Shiʿi and Christian places of worship, as well as Sunni shrines that it deemed idolatrous, such as the Mosque of the Prophet Jonah in Mosul. In early 2015 it turned its attention to the region’s ancient heritage. Videos were released showing members of ISIS destroying Assyrian artifacts in the Mosul museum and demolishing ruins at Nimrūd and Hatra in Iraq. In May 2015 ISIS took control of Palmyra, a city in the eastern Syrian desert that was the site of one of the Middle East’s largest collections of Greco-Roman ruins. By August ISIS fighters had begun demolishing monuments there.
Meanwhile, in mid-September 2014 ISIS launched an offensive into northern Syria in an attempt to gain control of the Kurdish areas on the Syria-Turkey border. Several months of heavy fighting between Kurdish militias and ISIS ensued, and tens of thousands of refugees fled into Turkey. Aided by air strikes and weapons deliveries from the international anti-ISIS coalition, Kurdish militias appeared to gain the upper hand in early 2015.
In late September 2014, meanwhile, the United States, leading an international coalition that included Jordan, the United Arab Emirates, Bahrain, and Saudi Arabia, expanded its air campaign to include targets in Syria. Russia undertook its own intervention in the Syrian Civil War in September 2015, launching a campaign of air strikes in support of the Assad regime over the objections of the U.S.-led coalition conducting air strikes against ISIS. Some of Russia’s air strikes hit ISIS, but the majority appeared to focus on other rebel groups in direct conflict with Assad’s forces.
The international and local forces were able to contain ISIS and begin to push it back. ISIS reached its peak by early 2015, controlling over 41,000 square miles in Iraq and Syria and ruling over at least eight million people, but by mid-2015 the group had begun losing ground.
