The Islamic State (IS), also known as the Islamic State of Iraq and the Levant (ISIL), the Islamic State of Iraq and Syria (ISIS), and by its Arabic acronym Daesh, is a transnational Salafi jihadist militant organisation and internationally unrecognised quasi-state. IS occupied a significant amount of territory in Iraq and Syria from 2013 to 2016, but lost most of it between 2017 and 2019. In 2014, the group proclaimed itself to be a worldwide caliphate and claimed religious and political authority over all Muslims worldwide, a claim not accepted by the vast majority of Muslims. It is designated as a terrorist organisation by the United Nations and many countries around the world, including Muslim countries.
By the end of 2015, its self-declared caliphate ruled an area with a population of about 12 million, where they enforced their extremist interpretation of Islamic law, managed an annual budget exceeding US$1 billion, and commanded more than 30,000 fighters. After a grinding conflict with American, Iraqi, and Kurdish forces, IS lost control of its Middle Eastern territories by 2019, subsequently reverting to insurgency from remote hideouts while continuing its propaganda efforts. These efforts have garnered a significant following in northern and Sahelian Africa, where IS still controls a significant territory. Originating in the Jaish al-Ta'ifa al-Mansurah founded by Abu Omar al-Baghdadi in 2004, the organisation (primarily under the Islamic State of Iraq name) affiliated itself with al-Qaeda in Iraq and fought alongside them during the 2003–2006 phase of the Iraqi insurgency. The group later changed its name to Islamic State of Iraq and Levant for about a year, before declaring itself to be a worldwide caliphate, called simply the Islamic State (الدولة الإسلامية, ad-Dawlah al-Islāmiyya).
During its rule in Syria and Iraq, the group became notorious for its brutality. It committed genocides against Yazidis and Iraqi Turkmen; engaged in persecution of Christians, Shia Muslims, and Mandaeans; publicised videos of beheadings of soldiers, journalists, and aid workers; and destroyed cultural sites. The group has perpetrated terrorist massacres in territories outside of its control, such as the November 2015 Paris attacks, the 2024 Kerman bombings in Iran, the 2024 Crocus City Hall attack in Russia. Lone wolf attacks inspired by the group have also taken place.
After 2015, the Iraqi Armed Forces and the Syrian Democratic Forces pushed back IS and degraded its financial and military infrastructure, assisted by advisors, weapons, training, supplies, and airstrikes by the American-led coalition and Iranian proxy forces, and later by Russian airstrikes, bombings, cruise missile attacks, and scorched-earth tactics across Syria, which focused mostly on razing Syrian opposition strongholds rather than IS bases. By March 2019, IS lost the last of its territories in West Asia, although its affiliates maintain a significant territorial presence in Africa as of 2025.
Name
The Islamic State, abbreviated IS, is also known as the Islamic State of Iraq and the Levant (ISIL EYE-sil), the Islamic State of Iraq and Syria (ISIS EYE-siss), and by its Arabic acronym Daesh (داعش, Dāʿish, IPA: [ˈdaːʕɪʃ]), and also as Dawlat al-Islām (دولة الإسلام). In April 2013, having expanded into Syria, the group adopted the name ad-Dawla al-Islāmiyya fī l-ʿIrāq wa-sh-Shām (الدولة الإسلامية في العراق والشام). As al-Shām is a region often compared with the Levant or the region of Syria, the group's name has been variously translated as "Islamic State of Iraq and al-Sham", "Islamic State of Iraq and Syria" (both abbreviated as ISIS), or "Islamic State of Iraq and the Levant" (abbreviated as ISIL). In 2014, Dar al-Ifta al-Misriyyah dubbed ISIS as "QSIS" for "al-Qaeda Separatists in Iraq and Syria", arguing that the group does not represent the vast majority of Muslims.
While the use of either one or the other acronym has been the subject of debate, the distinction between the two and its relevance has been considered less important. Of greater relevance is the name Daesh, which is an acronym of ISIL's Arabic name ad-Dawla al-Islamiyya fī l-ʿIrāq wa-sh-Shām, or Daesh. This name is widely used among the Muslim world, as well as ISIL's Arabic-speaking detractors, for example when referring to the group whilst speaking amongst themselves, although—and to a certain extent because—it is considered derogatory, as it resembles the Arabic words Daes ("one who crushes, or tramples down, something underfoot") and Dāhis (loosely translated as "one who sows discord"). Within areas under its control, ISIL considers use of the name Daesh punishable by flogging.
In late June 2014, the group renamed itself ad-Dawla al-Islāmiyya (lit. 'Islamic State' or IS), declaring itself a worldwide caliphate. The name "Islamic State" and the group's claim to be a caliphate have been widely rejected, with the UN, various governments, and mainstream Muslim groups refusing to use the new name. The group's declaration of a new caliphate in June 2014 and its adoption of the name "Islamic State" have been criticised and ridiculed by Muslim scholars and rival Islamists both inside and outside the territory it controls.
In a speech in September 2014, United States president Barack Obama said that ISIL was neither Islamic (on the basis that no religion condones the killing of innocents) nor a state (in that no government recognises the group as a state), while many object to using the name Islamic State owing to the far-reaching religious and political claims to authority which that name implies. The United Nations Security Council, the United States, Canada, Turkey, Australia, the United Kingdom, and other countries generally call the group ISIL, while much of the Arab world uses the Arabic acronym Dāʻish or Daesh. France's Foreign Minister Laurent Fabius said: "This is a terrorist group and not a state. I do not recommend using the term Islamic State because it blurs the lines between Islam, Muslims, and Islamists. The Arabs call it 'Daesh' and I will be calling them the 'Daesh cutthroats'." Retired general John Allen, the U.S. envoy appointed to co-ordinate the coalition; U.S. Army Lieutenant General James Terry, head of operations against the group; and Secretary of State John Kerry had all shifted towards use of the term Daesh by December 2014, which nonetheless remained a pejorative in 2021.
Purpose and strategy
Ideology
The ideology of the Islamic State has been described as being a hybrid of Salafism, Salafi jihadism, Islamic fundamentalism, Wahhabism, and Qutbism, as well as other doctrines.
According to Robert Manne, there is a "general consensus" that the ideology of the Islamic State is "primarily based upon the writings of the radical Egyptian theoretician Sayyid Qutb". The Muslim Brotherhood began the trend of political Islamism in the 20th century, seeking gradual establishment of a new Caliphate, a comprehensive Islamic society ruled by sharia law. Qutb's doctrines of jahiliyya (pre-Islamic ignorance), hakimiyya (divine sovereignty), and takfir of entire societies formed a radicalised vision of the Muslim Brotherhood's political Islam project. Qutbism became the precursor to all jihadist thought, from Abdullah Azzam to Zawahiri and to Daesh. Alongside Sayyid Qutb, the most invoked ideological figures of IS include Ibn Taymiyya, Abdullah Azzam, and Abu Bakr Naji.
Although IS claims to adhere to the Salafi theology of Ibn Taymiyyah, it rejects traditional Salafi interpretations as well as the four Sunni schools of law, and anathematises the majority of Salafis as heretics. IS ideologues rarely uphold adherence to Islamic scholarship and law manuals for reference, mostly preferring to derive rulings based on self-interpretation of the Qur'an and Muslim traditions.
Abu Omar al-Baghdadi, the first Emir of the Islamic State of Iraq, was radicalised as a Muslim Brotherhood member during his youth. Motaz Al-Khateeb states that religious texts and Islamic jurisprudence "alone cannot explain the emergence" of Daesh since the Muslim Brotherhood and Daesh "draw on the same Islamic jurisprudence" but "are diametrically opposite" in strategy and behaviour. Through the official statement of beliefs originally released by al-Baghdadi in 2007 and subsequently updated since June 2014, ISIL defined its creed as "a middle way between the extremist Kharijites and the lax Murji'ites". ISIL's ideology represents radical Jihadi-Salafi Islam, a strict, puritanical form of Sunni Islam. Muslim organisations like Islamic Networks Group (ING) in America have argued against this interpretation of Islam. ISIL promotes religious violence, and regards Muslims who do not agree with its interpretations as infidels or apostates.
According to Hayder al Khoei, IS's philosophy is represented by the symbolism in the Black Standard variant of the legendary battle flag of Muhammad that it has adopted: flag of IS shows the Seal of Muhammad within a white circle, with the phrase above it, "There is no god but Allah". This symbolism is said to symbolise IS's belief that it represents the restoration of the caliphate of early Islam, with all the political, religious, and eschatological ramifications that this would imply.
Abu Abdullah al-Muhajir, an Egyptian Jihadist theoretician and ideologue is considered as the key inspiration for early figures of IS. Al-Muhajir's legal manual on violence, Fiqh ad-Dima (The Jurisprudence of Jihad or The Jurisprudence of Blood), was adopted by IS as its standard reference for justifying its extraordinary acts of violence. The book has been described by counter-terrorism scholar Orwa Ajjoub as rationalising and justifying "suicide operations, the mutilation of corpses, beheading, and the killing of children and non-combatants". His theological and legal justifications influenced IS, al-Qaeda, and Boko Haram, as well as several other jihadi terrorist groups. Media outlets have compared his reference manual to Abu Bakr Naji's Management of Savagery, widely read among IS's commanders and fighters.
IS adheres to global jihadist principles and follows the hard-line ideology of al-Qaeda and many other modern-day jihadist groups.
For their guiding principles, the leaders of the Islamic State ... are open and clear about their almost exclusive commitment to the Wahhabi movement of Sunni Islam. The group circulates images of Wahhabi religious textbooks from Saudi Arabia in the schools it controls. Videos from the group's territory have shown Wahhabi texts plastered on the sides of an official missionary van.
According to The Economist, Saudi practices followed by the group include the establishment of religious police to root out "vice" and enforce attendance at Salah prayers, the widespread use of capital punishment, and the destruction or re-purposing of any non-Sunni religious buildings. Bernard Haykel has described IS leader Abu Bakr al-Baghdadi's creed as "a kind of untamed Wahhabism". Senior Saudi religious leaders have issued statements condemning IS, and attempting to distance the group from official Saudi religious beliefs. What connection, if any, there is between Salafi-Jihadism of IS and Wahhabism and Salafism proper is disputed. IS borrowed two elements of Qutbism and 20th century Islamism into its version of Wahhabi worldview. While Wahhabism shuns violent rebellion against earthly rulers, IS embraces political call to revolutions. While historically Wahhabis were not champion activists of a Caliphate, IS borrowed the idea of restoration of a global Caliphate.
Although the religious character of IS is mostly Wahhabi, it departs from the Wahhabi tradition in four critical aspects: dynastic alliance, call to establish a global caliphate, sheer violence, and apocalyptism. IS did not follow the pattern of the first three Saudi states in allying the religious mission of the Najdi ulema with the Al Saud family, rather they consider them apostates. The call for a global caliphate is another departure from Wahhabism. The caliphate, understood in Islamic law as the ideal Islamic polity uniting all Muslim territories, does not figure much in traditional Najdi writings. Ironically, Wahhabism emerged as an anti-caliphate movement.
Although violence was not absent in the First Saudi State, Islamic State's displays of beheading, immolation, and other forms of violence aimed at inspiring fear are not in imitation of early Saudi practices. They were introduced by Abu Musab Al-Zarqawi, former leader of Al-Qaeda in Iraq, who took inspiration from the Egyptian Jihadi scholar, Abu Abdallah Al Muhajir. It is the latter's legal manual on violence, popularly known as Fiqh ad-Dima (The Jurisprudence of Blood), that is the Islamic State's standard reference for justifying its acts of violence. The Islamic State's apocalyptic dimension also lacks a mainstream Wahhabi precedent.
IS aims to return to the early days of Islam, rejecting all innovations in the religion, which it believes corrupts its original spirit. It condemns later caliphates and the Ottoman Empire for deviating from what it calls pure Islam and seeks to revive the original Qutbist project of the restoration of a global caliphate that is governed by a strict Salafi-Jihadi doctrine. Following Salafi-Jihadi doctrines, IS condemns the followers of secular law as disbelievers, putting the current Saudi Arabian government in that category.
IS believes that only a legitimate authority can undertake the leadership of jihad and that the first priority over other areas of combat, such as fighting non-Muslim countries, is the purification of Islamic society. For example, IS regards the Palestinian Sunni group Hamas as apostates who have no legitimate authority to lead jihad and see fighting Hamas as the first step towards confrontation by IS with Israel.
Yemeni journalist Abdulelah Haider Shaye said:
The Islamic State was drafted by Sayyid Qutb, taught by Abdullah Azzam, globalized by Osama bin Laden, transferred to reality by Abu Musab al-Zarqawi, and implemented by al-Baghdadis: Abu Omar and Abu Bakr. [...]
The Islamic State added a focus on sectarianism to a layer of radical views. In particular, it linked itself to the Salafi-jihadi movement that evolved out of the Afghan jihad.
Islamic eschatology
One difference between IS and other Islamist and jihadist movements, including al-Qaeda, is the group's emphasis on eschatology and apocalypticism—that is, a belief in a final Day of Judgment by God. IS believes that it will defeat the army of "Rome" at the town of Dabiq.
The noted scholar of militant Islamism Will McCants writes:
References to the End Times fill Islamic State propaganda. It's a big selling point with foreign fighters, who want to travel to the lands where the final battles of the apocalypse will take place. The civil wars raging in those countries today [Iraq and Syria] lend credibility to the prophecies. The Islamic State has stoked the apocalyptic fire. ... For Bin Laden's generation, the apocalypse wasn't a great recruiting pitch. Governments in the Middle East two decades ago were more stable, and sectarianism was more subdued. It was better to recruit by calling to arms against corruption and tyranny than against the Antichrist. Today, though, the apocalyptic recruiting pitch makes more sense than before.
Goals
Since at latest 2004, a significant goal of the group has been the foundation of a Sunni Islamic state. Specifically, ISIL has sought to establish itself as a caliphate, an Islamic state led by a group of religious authorities under a supreme leader—the caliph—who is believed to be the successor to Muhammad. In June 2014, ISIL published a document in which it claimed to have traced the lineage of its leader al-Baghdadi back to Muhammad, and upon proclaiming a new caliphate on 29 June, the group appointed al-Baghdadi as its caliph. As caliph, he demanded the allegiance of all devout Muslims worldwide according to Islamic jurisprudence (fiqh).
ISIL has detailed its goals in its Dabiq magazine, saying it will continue to seize land and take over the entire Earth until its:
Blessed flag...covers all eastern and western extents of the Earth, filling the world with the truth and justice of Islam and putting an end to the falsehood and tyranny of jahiliyyah [state of ignorance], even if America and its coalition despise such.
According to German journalist Jürgen Todenhöfer, who spent ten days embedded with ISIL in Mosul, the view he kept hearing was that ISIL wants to "conquer the world", and that all who do not believe in the group's interpretation of the Quran will be killed. Todenhöfer was struck by the ISIL fighters' belief that "all religions who agree with democracy have to die", and by their "incredible enthusiasm"—including enthusiasm for killing "hundreds of millions" of people.
When the caliphate was proclaimed, ISIL stated: "The legality of all emirates, groups, states and organisations becomes null by the expansion of the khilafah's [caliphate's] authority and the arrival of its troops to their areas." This was a rejection of the political divisions in Southwestern Asia that were established by the UK and France during World War I in the Sykes–Picot Agreement.
All non-Muslim areas would be targeted for conquest after the Muslim lands were dealt with, according to the Islamist manual Management of Savagery.
Strategy
Documents found after the death of Samir Abd Muhammad al-Khlifawi, a former colonel in the intelligence service of the Iraqi Air Force before the US invasion who had been described as "the strategic head" of ISIL, detailed planning for the ISIL takeover of northern Syria, which made possible "the group's later advances into Iraq". Al-Khlifawi called for the infiltration of areas to be conquered with spies who would find out "as much as possible about the target towns: Who lived there, who was in charge, which families were religious, which Islamic school of religious jurisprudence they belonged to, how many mosques there were, who the imam was, how many wives and children he had and how old they were". Following this surveillance and espionage would come murder and kidnapping—"the elimination of every person who might have been a potential leader or opponent". In Raqqa, after rebel forces drove out the Assad regime and ISIL infiltrated the town, "first dozens and then hundreds of people disappeared".
Security and intelligence expert Martin Reardon has described IS's purpose as being to psychologically "break" those under its control, "so as to ensure their absolute allegiance through fear and intimidation", while generating "outright hate and vengeance" among its enemies. Jason Burke, a journalist writing on Salafi jihadism, has written that IS's goal is to "terrorize, mobilize [and] polarize". Its efforts to terrorise are intended to intimidate civilian populations and force governments of the target enemy "to make rash decisions that they otherwise would not choose". It aims to mobilise its supporters by motivating them with, for example, spectacular deadly attacks deep in Western territory (such as the November 2015 Paris attacks), to polarise by driving Muslim populations—particularly in the West—away from their governments, thus increasing the appeal of IS's self-proclaimed caliphate among them, and to: "Eliminate neutral parties through either absorption or elimination". Journalist Rukmini Maria Callimachi also emphasises IS's interest in polarisation or in eliminating what it calls the "grey zone" between the black (non-Muslims) and white (IS). "The gray is moderate Muslims who are living in the West and are happy and feel engaged in the society here."
A work published online in 2004 entitled Management of Savagery (Idarat at Tawahoush), described by several media outlets as influential on IS and intended to provide a strategy to create a new Islamic caliphate, recommended a strategy of attack outside its territory in which fighters would "Diversify and widen the vexation strikes against the Crusader-Zionist enemy in every place in the Islamic world, and even outside of it if possible, so as to disperse the efforts of the alliance of the enemy and thus drain it to the greatest extent possible."
The group has been accused of attempting to "bolster morale" and distract attention from its loss of territory to enemies by staging terror attacks abroad (such as the 2016 Berlin truck attack, the 6 June 2017 attacks on Tehran, the 22 May 2017 bombing in Manchester, and the 3 June 2017 attacks in London that IS claimed credit for).
Organisation
IS has been described as a militant group adhering to Salafi jihadism. Raqqa in Syria was under IS control from 2013 and in 2014 it became the group's de facto capital city. On 17 October 2017, following a lengthy battle that saw massive destruction to the city, the Syrian Democratic Forces (SDF) announced the full capture of Raqqa from IS.
Leadership and governance
From 2013 to 2019, IS was headed and run by Abu Bakr al-Baghdadi, the Islamic State's self-styled Caliph. Before their deaths, he had two deputy leaders, Abu Muslim al-Turkmani for Iraq and Abu Ali al-Anbari (also known as Abu Ala al-Afri) for Syria, both ethnic Turkmen. Advising al-Baghdadi were a cabinet of senior leaders, while its operations in Iraq and Syria are controlled by local 'emirs,' who head semi-autonomous groups that the Islamic State refers to as its provinces. Beneath the leaders are councils on finance, leadership, military matters, legal matters (including decisions on executions) foreign fighters' assistance, security, intelligence and media. In addition, a shura council has the task of ensuring that all decisions made by the governors and councils comply with the group's interpretation of sharia. While al-Baghdadi had told followers to "advise me when I err" in sermons, according to observers "any threat, opposition, or even contradiction is instantly eradicated".
According to Iraqis, Syrians, and analysts who study the group, almost all of IS's leaders—including the members of its military and security committees and the majority of its emirs and princes—are former Iraqi military and intelligence officers, specifically former members of Saddam Hussein's Ba'ath government who lost their jobs and pensions in the de-Ba'athification process after that regime was overthrown. The former Chief Strategist in the Office of the Coordinator for Counterterrorism of the US State Department, David Kilcullen, has said, "There undeniably would be no Isis if we had not invaded Iraq." It has been reported that Iraqis and Syrians have been given greater precedence over other nationalities within IS because the group needs the loyalties of the local Sunni populations in both Syria and Iraq in order to be sustainable. Other reports, however, have indicated that Syrians are at a disadvantage to foreign members, with some native Syrian fighters resenting "favouritism" allegedly shown towards foreigners over pay and accommodation.
In August 2016, media reports based on briefings by Western intelligence agencies suggested that IS had a multilevel secret service known in Arabic as Emni, established in 2014, that has become a combination of an internal police force and an external operations directorate complete with regional branches. The unit was believed to be under the overall command of IS's most senior Syrian operative, spokesman and propaganda chief Abu Mohammad al-Adnani until his death by airstrike in late August 2016.
On 27 October 2019, the United States conducted a special operation targeting al-Baghdadi's compound in Barisha, Idlib, Northwest Syria. The attack resulted in al-Baghdadi's death; caught by surprise and unable to escape, al-Baghdadi detonated a suicide vest, deliberately killing both himself and two children who had been living in the compound prior to the assault. U.S. president Donald Trump stated in a televised announcement that Baghdadi had, in fact, died during the operation and that American forces used support from helicopters, jets and drones through airspace controlled by Russia and Turkey. He said, "Russia treated us great... Iraq was excellent. We really had great cooperation" and Turkey knew they were going in. He thanked Turkey, Russia, Syria, Iraq and the Syrian Kurdish forces for their support. The Turkish Defence Ministry also confirmed on Sunday that Turkish and U.S. military authorities exchanged and coordinated information ahead of an attack in Syria's Idlib. Fahrettin Altun, a senior aide to Turkish president Tayyib Erdogan, also stated, among other things, "Turkey was proud to help the United States, our NATO ally, bring a notorious terrorist to justice" and that Turkey "will continue to work closely with the United States and others to combat terrorism in all its forms and manifestations." Kremlin spokesman Dmitry Peskov declined to say if the United States had told Russia about the raid in advance but said that its result if confirmed, represented a serious contribution by the United States to combat terrorism. Russia had previously claimed Baghdadi was killed in May 2017 by their airstrike.
In September 2019, a statement attributed to IS's propaganda arm, the Amaq news agency, claimed that Abdullah Qardash was named as al-Baghdadi's successor. Analysts dismissed this statement as a fabrication, and relatives were reported as saying that Qardash died in 2017. Rita Katz, a terrorism analyst and the co-founder of SITE Intelligence, noted that the alleged statement used a different font when compared to other statements and it was never distributed on Amaq or IS channels.
On 29 October 2019, Trump stated on social media that al-Baghdadi's "number one replacement" had been killed by American forces, without giving a name. A U.S. official later confirmed that Trump was referring to IS spokesman and senior leader Abul-Hasan al-Muhajir, who was killed in a U.S. airstrike in Syria two days earlier. On 31 October, IS named Abu Ibrahim al-Hashemi al-Qurayshi as Baghdadi's successor. On 3 February 2022, it was reported by a US official that al-Hashimi killed himself and members of his family by triggering an explosive device, during a counter-terrorism raid by the US Joint Special Operations Command. On 30 November 2022, IS announced that their next leader, Abu al-Hasan al-Hashimi al-Qurashi, had been killed in battle and named a successor, providing no additional information other than his pseudonym, Abu al-Hussein al-Husseini al-Qurashi, who was believed to be the Islamic State's first Syrian chief. A spokesman for U.S. Central Command confirmed that IS's leader had been killed in mid-October by anti-government rebels in southern Syria. On 16 February 2023, senior IS leader Hamza al-Homsi blew himself up in a U.S.-led raid in Syria. On 23 April 2023, IS leader Abu al-Hussein al-Husseini al-Qurashi was killed in an attack on his residence at Jindires, in the northwestern Idlib Governorate. Turkey claimed responsibility for his death, while the Islamic State claimed that al-Husseini al-Qurashi was killed in a shootout with Tahrir al-Sham (HTS) forces. Subsequently, the Islamic State named Abu Hafs al-Hashimi al-Qurashi as their new leader. In late August 2025, US Special Forces carried out a helicopter raid at Atmeh, near the Turkish border region. They killed two senior IS leaders in the raid, including a figure who was believed to be next-in-line for the Islamic State leadership. Analysts believe that the Islamic State is headquartered in the northwestern Idlib Governorate region, near the Turkish border, ever since the group lost their last territorial stronghold at Al-Baghuz Fawqani in Spring 2019.
Civilians in Islamic State-controlled areas
In 2014, The Wall Street Journal estimated that eight million people lived in the Islamic State. The United Nations Commission on Human Rights has stated that IS "seeks to subjugate civilians under its control and dominate every aspect of their lives through terror, indoctrination, and the provision of services to those who obey". Civilians, as well as the Islamic State itself, have released footage of some of the human rights abuses.
Social control of civilians was imposed with IS's strict interpretation of sharia law, enforced by morality police forces known as Al-Hisbah and the all-women Al-Khanssaa Brigade, a general police force, courts, and other entities managing recruitment, tribal relations, and education. Al-Hisbah was led by Abu Muhammad al-Jazrawi.
In 2015, IS published a penal code including floggings, amputations, crucifixions, etc.
Military
Number of combatants
Estimates of the size of IS's military have varied widely, from tens of thousands up to 200,000.
In early 2015, journalist Mary Anne Weaver estimated that half of IS fighters were foreigners. A UN report estimated a total of 15,000 fighters from over 80 countries were in IS's ranks in November 2014. US intelligence estimated an increase to around 20,000 foreign fighters in February 2015, including 3,400 from the Western world. In September 2015, the CIA estimated that 30,000 foreign fighters had joined IS.