Islamic State

The Islamic State (IS) is a transnational jihadist terrorist organization that seeks to establish a state governed by its extreme interpretation of Islamic law. It grew out of insurgent networks in Iraq and expanded during the Syrian civil war. At its height, it controlled large areas of Iraq and Syria, governed millions of people through coercion and violence, and directed or inspired attacks abroad.

In June 2014, the group declared a caliphate and called on Muslims to recognize its leader, Abu Bakr al-Baghdadi, as caliph. Its forces captured Mosul and other major population centers, exploiting political instability, sectarian conflict and weaknesses in Iraqi and Syrian state institutions. The organization lost its last territorial stronghold in Syria in 2019, but it continued as an insurgency and maintained affiliates in several regions.

IS carried out mass executions, suicide bombings, beheadings and attacks on civilians. It persecuted Christians, Yazidis, Shiites, Sunnis who opposed its rule and other minorities. The group enslaved Yazidi women and girls and committed genocide against the Yazidi people. Its territorial defeat ended its claim to govern a contiguous state, not its capacity to organize attacks or inspire extremist violence.

Name and terminology

The organization has used several names as it changed its territorial and political claims. It began as al-Qaeda in Iraq, later adopted the name Islamic State of Iraq, and in 2013 announced a merger with an armed group in Syria under the name Islamic State of Iraq and the Levant. It subsequently used the name Islamic State and proclaimed a caliphate. The abbreviations ISIS and ISIL reflect different translations of the Arabic term for the Levant.

Many governments and media organizations use “Islamic State” or “ISIS.” The Arabic acronym Daesh is also used by opponents, and the group rejects it. The terminology is politically charged because the organization’s claim to represent Islam is rejected by many Muslim scholars and communities. Its ideology is a specific extremist political program, not a representation of Islam as a whole.

The group’s names reflect its changing territorial ambitions. Its 2014 declaration claimed authority over Muslims worldwide and rejected national borders established by modern states. That claim was not recognized by any government and was rejected by mainstream Muslim religious authorities. The organization’s use of the word “state” described its aspiration and period of territorial control, not internationally recognized sovereignty.

Origins and history

Roots in Iraq

The group’s roots lie in the insurgency that followed the 2003 United States-led invasion of Iraq. Abu Musab al-Zarqawi established a jihadist organization that became aligned with al-Qaeda and was known as al-Qaeda in Iraq. It carried out suicide bombings, attacks on Iraqi civilians and security forces, and violence against Shiite communities. Its strategy sought to intensify sectarian conflict and undermine the new Iraqi government.

After al-Zarqawi was killed in a United States airstrike in 2006, the organization announced the formation of the Islamic State of Iraq under Abu Omar al-Baghdadi. It combined al-Qaeda-linked militants with other insurgents and claimed to establish a state in parts of Iraq. The organization faced opposition from Sunni tribal leaders and former insurgents who formed the Awakening Councils, which cooperated with American and Iraqi forces. By 2009, the group had lost much of its territory and many leaders.

Abu Omar al-Baghdadi was killed in 2010. Abu Bakr al-Baghdadi succeeded him and rebuilt the network. The withdrawal of most United States forces from Iraq, political exclusion of Sunni communities and conflict between the government and its opponents created conditions in which the group could regain strength. It recruited experienced insurgents, developed covert cells and used prisons and smuggling routes to rebuild its organization.

Expansion into Syria and territorial conquest

The Syrian civil war, which began in 2011, gave the organization a new arena. Its fighters crossed the border and established a branch in Syria. In 2013, al-Baghdadi announced that the Iraqi and Syrian branches would merge. The Syrian group’s leader rejected the merger, leading to a split between the Islamic State and al-Qaeda. The dispute became violent, with both organizations competing for territory, recruits and authority.

In June 2014, IS captured Mosul, Iraq’s second-largest city, after Iraqi security forces collapsed. It seized weapons, money and government facilities and advanced across northern and western Iraq. In Syria, it captured Raqqa and other areas. The group exploited Sunni grievances, weak state institutions and the fragmentation of opposition forces. Its rapid expansion shocked regional governments and international observers.

On 29 June 2014, IS declared a caliphate and renamed itself the Islamic State. Al-Baghdadi appeared in Mosul and called on Muslims to pledge allegiance. The declaration aimed to legitimize the organization as a universal authority and recruit foreign fighters. It also rejected the existing borders and political systems of the region. The claim was denounced by Muslim scholars and rejected by governments worldwide.

The organization imposed a coercive administration in territory under its control. It established courts, police, taxation, schools and public services, while enforcing strict social rules and punishing dissent. Its bureaucratic systems helped collect revenue and regulate daily life. These institutions were subordinate to a violent ideology that denied basic rights and used fear to secure compliance.

Military defeat and insurgency

A United States-led coalition began airstrikes against IS in Iraq in 2014 and expanded operations into Syria. Iraqi forces, Kurdish forces including the Peshmerga, Syrian Democratic Forces and other local groups fought the organization on the ground. The coalition’s airpower, intelligence and training supported these campaigns. The organization lost major cities and supply routes over several years.

Iraqi forces retook Mosul in 2017 after months of urban combat. The battle caused extensive civilian casualties and destruction. IS fighters used tunnels, booby traps, suicide attacks and human shields to slow the advance. Similar campaigns pushed the group from Raqqa and other Syrian cities. The group’s loss of territory undermined its claim to be a functioning state and deprived it of tax revenues and oil infrastructure.

In March 2019, the Syrian Democratic Forces captured Baghouz, the last significant territorial enclave held by IS in Syria. Al-Baghdadi was killed in a United States raid in October 2019. The territorial caliphate had collapsed, but the organization retained clandestine cells and a capacity to conduct insurgent attacks. It shifted toward ambushes, assassinations, bombings and prison raids.

IS has continued to operate in Iraq and Syria and has developed affiliates in Africa and Asia. These branches vary in their relationship to the central organization and in their local objectives. Some pledge allegiance to the central leadership, while others operate with considerable autonomy. Territorial losses did not end the organization; they changed its methods and reduced its ability to govern openly.

Ideology and strategy

IS follows a violent Salafi-jihadist ideology that combines a literalist interpretation of scripture with the political objective of restoring a caliphate. It regards many Muslims who disagree with its doctrine as apostates and uses this judgment to justify their killing. The organization has targeted Shiites, Sufis, Christians, Yazidis and Sunni Muslims who resisted its authority.

The group’s ideology is not representative of Sunni Islam. Muslim scholars and institutions across the world have condemned its interpretation and violence. Its selective use of religious texts and historical narratives served political goals, including recruitment, discipline and territorial expansion. A factual account identifies the group’s own claims without treating them as authoritative statements about Islam.

IS’s strategy aimed to provoke sectarian conflict, weaken states and establish control over territory. Attacks on civilians and religious minorities were intended to spread fear and deepen social divisions. The group used mass violence as a tool of governance, punishment and propaganda. Its actions included public executions, destruction of religious sites and the systematic enslavement of Yazidis.

Its military approach combined conventional formations with insurgent tactics. While holding territory, IS fielded infantry, armored vehicles and artillery captured from government forces. It also used suicide bombers, vehicle-borne explosives, tunnels and improvised weapons. After losing territory, it returned to guerrilla operations and relied on cells concealed among civilian populations.

Organization and leadership

Leadership and governance

Abu Bakr al-Baghdadi led the organization from 2010 until his death in 2019. He held the title of caliph after the 2014 declaration and was presented as the supreme religious and political authority. Senior councils and regional leaders supported his rule. The organization’s succession has been secretive, and leaders have been killed or captured through military operations.

During its territorial period, IS created administrative divisions called provinces and appointed governors. Its bureaucracy collected taxes, regulated commerce and distributed some services. The organization imposed religious courts and police, and used surveillance and informants to enforce control. Residents faced severe penalties for disobedience, including imprisonment, torture and execution.

Governance varied across territories and over time. Some local officials were experienced administrators, while others were military commanders. The organization recruited civil servants from existing institutions and compelled them to work under its authority. It used public services to portray itself as a state, but its governance depended on coercion and the denial of basic freedoms.

Military organization and affiliates

IS organized combat units, intelligence networks, police and specialized security divisions. Its forces included local recruits and foreign fighters. The organization used foreign volunteers in combat, administration and propaganda. Recruitment was supported by online media and personal networks, and fighters traveled from many countries to join the caliphate.

Affiliates emerged in North Africa, the Sahel, West Africa, the Sinai Peninsula, Afghanistan and other regions. Some originated as local jihadist organizations that pledged allegiance to IS; others developed from internal splits. Affiliates have pursued local conflicts and may not receive direct orders from the central leadership. Their alignment has nonetheless expanded the organization’s global profile and created threats beyond Iraq and Syria.

Finances and territorial economy

IS financed its territorial rule through oil sales, taxation, extortion, confiscation, kidnapping, looting and control of agricultural land. It seized cash from banks when it captured cities and imposed fees on businesses, transport and residents. These revenue streams made it one of the wealthiest terrorist organizations during its period of territorial control.

Oil production and smuggling were important sources of income. The group controlled fields and refineries in Iraq and Syria and sold oil through intermediaries. It also taxed local commerce and agricultural production. Revenue was used to pay fighters, purchase weapons, administer territory and fund propaganda. The organization’s financial system relied on coercive extraction rather than productive economic development.

IS seized antiquities and sold some through illicit networks. It also confiscated property from people who fled or were targeted as minorities. The organization’s treatment of Yazidis included forced conversion, enslavement and the sale of women and girls. These acts were part of a genocidal campaign and generated both revenue and terror.

Coalition airstrikes targeted oil infrastructure, financial offices and cash storage. The group’s loss of territory sharply reduced its income. It adapted by relying on extortion and clandestine networks, though these methods could not sustain the same scale of military and administrative control. Current affiliate finances vary by region and local opportunity.

Mass violence and persecution

IS committed widespread atrocities against civilians. Its forces executed prisoners, abducted women and children, used suicide bombings and targeted religious communities. The organization publicized some killings to intimidate opponents and recruit supporters. Its crimes were investigated by international bodies, journalists and human rights organizations.

In 2014, IS attacked the Yazidi population of Sinjar. It killed thousands of people, abducted women and children, and forced many to flee. Women and girls were sold or held in sexual slavery; boys were separated from families and subjected to indoctrination and combat training. United Nations investigators concluded that IS committed genocide against the Yazidi people, alongside crimes against humanity and war crimes.

The group also persecuted Christians and other minorities, forcing them to flee, convert, pay special taxes or face death. It destroyed churches, mosques, shrines and ancient cultural sites. Shiite Muslims were targeted in mass-casualty attacks and executions. Sunni communities that resisted IS faced collective punishment and massacres.

IS carried out attacks beyond the territories it controlled. It claimed responsibility for or inspired attacks in Europe, North Africa, the Middle East and South Asia. These operations targeted civilians at concerts, transport hubs, hotels, religious sites and public spaces. The group used propaganda to encourage supporters to attack, even when they had no direct contact with its leadership.

Mass graves and documentation of detention sites have provided evidence of atrocities. Investigations have sought to identify perpetrators and preserve testimony. Survivors and families continue to seek accountability and the return of missing people. The scale of the crimes requires careful historical record and legal prosecution, not euphemism or normalization.

Communications and propaganda

IS built a sophisticated media operation that produced videos, magazines, photographs and online messages. Its outlets portrayed a functioning state, celebrated military victories and threatened opponents. Videos of executions were designed to shock and attract attention. The group also used social media to recruit foreign fighters and circulate ideological material.

Propaganda was tailored to different audiences. Some messages emphasized religious identity and apocalyptic themes; others highlighted social services or battlefield success. Foreign recruits were promised purpose, status and participation in a historical project. In practice, many encountered coercion, violence and a rigid hierarchy.

Governments and technology companies sought to remove IS content and disrupt recruitment networks. The group adapted by using encrypted communications, mirror sites and decentralized supporters. Its media reach declined after the fall of its territory, but affiliated groups and supporters continued to disseminate propaganda online.

International response and designation

The United Nations Security Council has listed IS and its predecessor organizations under the sanctions regime for al-Qaeda. Member states are required to freeze assets, restrict travel and prevent arms transfers. The United States, European Union and many national governments designate the organization as terrorist. These measures reflect its attacks on civilians, transnational operations and mass atrocities.

A global coalition formed to defeat IS and included dozens of countries. Members provided airstrikes, training, intelligence, logistics and humanitarian assistance. Local partners conducted most ground fighting. The campaign ended the group’s territorial rule but did not eliminate its underground networks or affiliates.

Religious authorities and Muslim organizations worldwide rejected IS’s claims to religious legitimacy. Governments also pursued prosecutions of returning fighters and investigations into crimes. International agencies supported the documentation of atrocities and the recovery of survivors. These efforts continue because the organization’s members remain dispersed and many victims are still missing.

Assessment and continuing threat

IS’s rapid territorial expansion reflected the collapse of state authority in parts of Iraq and Syria, sectarian political exclusion and the organization’s ability to exploit war. Its declared caliphate was a short-lived project, but it demonstrated how an armed group could combine insurgency, conventional warfare, bureaucracy and propaganda.

The organization’s territorial defeat was a major military achievement, yet it did not remove the conditions that enabled its rise. Weak governance, unresolved grievances, conflict and unprotected communities can provide opportunities for insurgent recruitment. IS continues to exploit insecurity through attacks and local alliances, while its affiliates adapt to regional conditions.

IS remains a terrorist organization responsible for mass murder, genocide, enslavement and attacks on civilians. Its ideology has been rejected by mainstream Muslim authorities, and its claim to govern has no international legitimacy. Understanding the group requires recognizing both its military organization and the crimes at the core of its rule.