It began as a splinter group of al Qaeda.
Also known as the Islamic State of Iraq and the Levant (ISIL) and the Islamic State of Syria (IS).
ISIS seeks to establish an Islamic state known as a caliphate across Iraq, Syria, and beyond.
The group uses Sharia Law, which is rooted in eighth-century Islam, to create a society that reflects the region’s ancient past.
ISIS promotes reactionary politics and religious fundamentalism through modern tools such as social media. As their leaders preach a return to the early days of Islam, fighters destroy holy sites and valuable antiquities.
ISIS earns money through oil production and smuggling, taxes, ransoms from kidnappings, the sale of stolen artifacts, extortion, and crop control.
The group announced that the leader of ISIS has been Abu al-Hasan al-Hashimi al-Qurashi since March 2022, but this is thought to be an assumed name. Al-Qurashi ascended to the throne following the death of Abu Ibrahim al-Hashimi al-Qurayshi, who served as leader from 2019 until his death in February 2022.
Abu Musab al-Zarqawi establishes al Qaeda in Iraq in 2004. (AQI).
2006 – Al Qaeda in Iraq, led by Zarqawi, attempts to incite a sectarian war against the Shia majority.
Zarqawi is killed in a US strike on June 7, 2006. Abu Ayyub al-Masri succeeds him as AQI leader.
Masri announces the formation of the Islamic State of Iraq (ISI) and appoints Abu Omar al-Baghdadi as its leader in October 2006.
After Abu Omar al-Baghdadi and Masri are killed in a joint US-Iraqi operation in April 2010, Abu Bakr al-Baghdadi takes over as leader of the ISI.
April 2013 – ISI announces the incorporation of Jabhat al-Nusra, also known as the al-Nusra Front, an al Qaeda-backed militant group in Syria. Baghdadi claims that his organization will now be known as the Islamic State of Iraq and the Levant (ISIL or ISIS).
ISIS seizes control of Falluja in January 2014.
After months of infighting between al-Nusra Front and ISIS, Al Qaeda renounces its ties to ISIS on February 3, 2014.
According to the London-based monitoring group Syrian Observatory for Human Rights, ISIS kidnaps more than 140 Kurdish schoolboys in Syria and forces them to study radical Islamic theology.
ISIS seizes Mosul and Tikrit on June 9-11, 2014.
ISIS seizes control of Al-Qaim, a border town with Syria, as well as three other Iraqi towns on June 21, 2014.
June 28, 2014 – Iraqi Kurdistan restricts refugee border crossings into the region.
June 29, 2014 – ISIS declares the establishment of an Islamic caliphate (Islamic state) that abolishes all state borders, making Baghdadi the self-proclaimed ruler of the world’s estimated 1.5 billion Muslims. The group also announces a rebranding as the Islamic State (IS).
June 30, 2014 – The Pentagon announces that the United States will send an additional 300 troops to Iraq, bringing the total number of US troops in the country to nearly 800. Troops and military advisers are sent to Iraq to assist Iraqi security forces and to protect the US Embassy and Baghdad International Airport.
ISIS seizes Syria’s largest oilfield and a gas field in Homs Province in July 2014, storming the facility and killing dozens of workers. Militants seize control of a 90-mile stretch of Syrian towns stretching from Deir Ezzor to the Iraqi border. They blow up Jonah’s tomb in Mosul, a holy site dating back to the eighth century BC.
ISIS fighters launch an attack on the northern Iraqi town of Sinjar, which is home to the Yazidis, a religious minority group. Over 30,000 Yazidi families have become stranded in the Sinjar Mountains. According to a Yazidi lawmaker, 500 men have been killed, 70 children have died from thirst, and women are being sold into slavery.
Two US jet fighters bomb ISIS artillery units in Iraq on August 8, 2014. If necessary, US President Barack Obama authorizes “targeted airstrikes” to protect US personnel and prevent potential genocide against minority groups.
ISIS posts a video of the beheading of US journalist James Foley, who has been missing in Syria since 2012.
ISIS releases a video showing the beheading of US journalist Steven Sotloff on September 2, 2014. The apparent executioner has the same British accent as the man who allegedly murdered Foley.
September 11, 2014 – The CIA announces that the number of ISIS fighters may be three times higher than previously estimated.
ISIS posts a video showing the apparent execution of British aid worker David Haines on September 13, 2014.
The United States conducts airstrikes against ISIS on September 23, 2014.
ISIS releases a video showing the apparent beheading of British hostage Alan Henning on October 3, 2014.
On November 3, 2014, the Iraqi government announced that ISIS militants had executed 322 members of a Sunni tribe.
The UN Independent International Commission of Inquiry on Syria concludes that ISIS committed war crimes and crimes against humanity on November 14, 2014.
ISIS posts a video purporting to show a dead American hostage, Peter Kassig, on November 16, 2014.
According to US diplomatic officials, coalition airstrikes have killed an estimated 6,000 ISIS fighters.
January 24, 2015 – An ISIS video and audio appear to show the beheaded body of Japanese hostage Haruna Yukawa.
ISIS releases a video purporting to show the decapitated body of a second Japanese hostage, Kenji Goto, on January 31, 2015.
ISIS appears to have posted video and still images of Jordanian pilot Moath al-Kasasbeh being burned alive while imprisoned in a cage on February 3, 2015.
Jordanian fighter jets launch airstrikes over Syria, reportedly targeting ISIS training camps as well as arms and ammunition depots in Raqqa. ISIS claims that the airstrikes killed American hostage Kayla Jean Mueller the next day. ISIS posts a picture of a collapsed building and claims Mueller is buried beneath it.
Mueller’s family announces her death on February 10, 2015, after receiving confirmation from ISIS, and includes a photo of her wrapped in a burial shroud.
Obama asks the US Congress to formally authorize the use of military force against ISIS on February 11, 2015.
ISIS releases a video in which militants appear to behead more than a dozen Egyptian Christians on a Libyan beach on February 15, 2015. The following day, Egyptian warplanes attack ISIS targets in Libya.
ISIS releases a video purporting to show at least 21 Kurdish Peshmerga fighters in cages being carried down Iraqi streets on February 22, 2015.
February 26, 2015 – Mohammed Emwazi, a Kuwaiti-born Londoner, has been identified as Jihadi John, the disguised man with a British accent who appeared in ISIS videos as the executioner of Western hostages. ISIS releases a video of its fighters destroying antiquities at the Mosul Museum on the same day.
ISIS posts images of a man being thrown off a building in Raqqa, Syria, in March 2015. He was accused of being gay. There have been at least a half-dozen documented cases of ISIS killing gay men.
ISIS releases 19 Christian prisoners on March 1, 2015. Except for one, they are said to be from a group of 220 Assyrians apprehended in northern Syria.
March 7, 2015 – Boko Haram, a Nigeria-based radical Islamic group, pledges allegiance to ISIS in an audio message purportedly from leader Abubakar Shekau. After a few days, an ISIS spokesman claims the caliphate has spread to Western Africa.
Iraqi forces retake the majority of Tikrit on March 12, 2015. ISIS blows up the Iraqi army headquarters north of Ramadi in western Iraq, killing at least 40 Iraqi soldiers.
Iraqi forces, aided by Shiite militiamen, seize full control of Tikrit on April 1, 2015.
According to Iraqi Kurdistan officials, ISIS has released over 200 Yazidi women and children, as well as the sick and elderly.
ISIS releases a video purporting to show militants beheading two groups of prisoners in Libya on April 19, 2015. According to the Ethiopian government, 30 of the victims were Ethiopian citizens.
According to US officials, a key ISIS leader was killed during a US Special Operations raid in Syria on May 16, 2015. His wife is apprehended, and the raid yields valuable information about ISIS’s structure and communications.
May 17, 2015 – ISIS seizes control of Ramadi, the largest city in western Iraq, following the withdrawal of government security forces from a military base.
May 21, 2015 – ISIS seizes control of Palmyra, a UNESCO World Heritage Site in Syria. According to the Syrian Observatory for Human Rights, it was the last border crossing between Syria and Iraq under Syrian control.
The US State Department issues its annual terrorism report on June 19, 2015, declaring that ISIS is becoming a greater threat than al Qaeda. According to the report, the frequency and ferocity of ISIS attacks are concerning.
June 24, 2015 – According to the Syrian government, ISIS militants have destroyed two Muslim holy sites in Palmyra. The group allegedly attacked a 500-year-old shrine as well as a tomb where a descendant of the Prophet Mohammed’s cousin was buried.
A gunman kills at least 38 people at a beachfront Tunisian hotel on June 26, 2015, and a bomb kills at least 27 people at a mosque in Kuwait. The attacks have been claimed by ISIS.
ISIS launches simultaneous attacks on five Egyptian military checkpoints on July 1, 2015, killing 17 Egyptian soldiers and injuring 30 others. The Egyptian military claims that 100 terrorists have been killed in the fighting.
The Syrian Observatory for Human Rights reports receiving a video showing ISIS militants executing 25 captives in Palmyra on July 4, 2015.
July 17, 2015 – As Iraqis in Khan Bani Saad celebrate Eid al-Fitr, the end of the Ramadan fast, ISIS detonates an ice truck bomb in a crowded marketplace, killing at least 120 people and injuring at least 140 more.
ISIS destroys Palmyra’s nearly 2,000-year-old Baalshamin temple in August 2015. The destruction of the temple is considered a “war crime” by UNESCO, the United Nations’ cultural organization.
The Obama administration announces the deployment of US Special Operations forces to join the fight against ISIS in northern Syria on October 30, 2015. According to the White House, fewer than 50 troops will be deployed to Syria. An additional 450 American troops will be sent to Syria over the next 14 months to help train local anti-ISIS forces.
The Pentagon announces a remote control drone strike targeting Emwazi, also known as “Jihadi John,” on November 12, 2015. ISIS later confirms Emwazi’s death.
On November 12, 2015, two suicide bombers detonated in the Bourj al-Barajneh district of southern Beirut, killing over 40 people and injuring hundreds more. The attack has been claimed by ISIS.
After two days of fighting, Kurdish forces liberate the Iraqi town of Sinjar from ISIS on November 13, 2015. The Kurds had the support of coalition air power.
On November 13, 2015, three teams of ISIS suicide bombers with guns attacked six locations in Paris, killing at least 130 people and injuring 494 others.
December 10, 2015 – A US-led coalition spokesman confirms that ISIS Finance Minister Abu Saleh was killed in an airstrike in late November in Iraq.
According to an Iraqi military spokesman, Iraqi troops retake the city of Ramadi from ISIS on December 28, 2015.
ISIS releases a video purporting to show the final messages of the Paris attackers on January 24, 2016.
Multiple attacks in Homs and southern Damascus kill at least 122 people and injure many more, according to Syria’s state-run SANA news agency. ISIS has taken responsibility.
March 22, 2016 – Attacks on a Brussels airport and a subway station kill over 30 people and injure over 270 more. ISIS claims the attacks were carried out by its “fighters.”
The Pentagon confirms the death of ISIS’ finance minister, Abd al-Rahman Mustafa al-Qaduli, on March 25, 2016.
June 26, 2016 – A senior Iraqi general declares on state television that the battle for Falluja is over, as Iraqi troops retake the city’s final ISIS stronghold.
On June 28, 2016, three attackers arrive in a taxi at Turkey’s Istanbul Ataturk Airport, open fire, and then blow themselves up, killing at least 44 people and injuring more than 230. US officials believe Akhmed Chatayev, a terrorist from Russia’s North Caucasus region and a well-known ISIS lieutenant, directed the three attackers.
On July 1-2, 2016, attackers stormed the Holey Artisan Bakery cafe in a diplomatic enclave of Dhaka, Bangladesh’s capital. Before authorities raid the restaurant and end the nearly 11-hour standoff, gunmen kill 20 hostages and two police officers. Although ISIS claims responsibility for the attack, Bangladeshi officials claim it was carried out by homegrown militants. After photos purportedly showing the inside of the cafe and dead hostages were posted on an ISIS-affiliated website, US officials focused on ISIS as the perpetrator.
On July 3, 2016, a suicide car bomb detonates in Baghdad’s busy shopping district, killing at least 292 people and injuring 200 more. It is Iraq’s deadliest single attack since 2003. ISIS has taken responsibility.
ISIS spokesman Abu Muhammad al-Adnani was killed in the Aleppo area of Syria, according to a statement from the terror group and its Amaq news agency. Without confirming Adnani’s death, the Pentagon confirms that coalition forces conducted an airstrike targeting him in al Bab, Syria.
September 16, 2016 – Pentagon Press Secretary Peter Cook confirms that a US air strike targeted and killed ISIS’s chief spokesman, Wael Adel Salman, aka Abu Muhammad al-Furqan. According to Cook, Salman was the ISIS minister of information, in charge of overseeing the production of “terrorist propaganda videos showing torture and executions.”
October 17, 2016 – Iraqi Prime Minister Haider al-Abadi issues a televised statement announcing the start of the mission to retake Mosul, Iraq’s last remaining ISIS stronghold.
Suicide bombers attack sleeping cadets at a police training academy in Pakistan on October 24, 2016, killing 61 and injuring 117. ISIS claims responsibility, releasing a photo of the three alleged attackers, but Pakistani military leaders believe the attack was carried out by a Pakistan-based group, Lashkar-e-Jhangvi.
ISIS claims responsibility for two deadly bombings targeting Coptic Christian churches in Egypt on Palm Sunday. The blasts have killed at least 49 people and injured 119 others.
The US military drops its most powerful non-nuclear bomb on an ISIS compound in Afghanistan on April 13, 2017. An Afghan official later told CNN that the blast killed 94 militants.
May 26-28, 2017 – More than 200 civilians are killed by ISIS militants in Mosul, according to the UN.
May 26, 2017 – Buses carrying Coptic Christians in Egypt are attacked by assailants, who fatally shoot at least 29. ISIS claims responsibility.
July 10, 2017 – Mosul is liberated from ISIS.
October 17, 2017 – ISIS loses control of its self-declared capital, the Syrian city of Raqqa. US-backed forces fighting in Raqqa say “major military operations” have ended, though there are still pockets of resistance in the city.
The Pentagon announces that there are 5,200 American troops in Iraq and 2,000 troops in Syria as of December 6, 2017. According to the Pentagon, troop levels are declining as Iraqi and Syrian Democratic Forces liberate approximately 97% of the territory and people in ISIS’s declared caliphate.
The Iraqi military claims to have “fully liberated” all of Iraq’s territory from “ISIS terrorist gangs” and retaken full control of the Iraqi-Syrian border. It took more than three years and approximately 25,000 coalition airstrikes to defeat ISIS in Iraq.
According to the UN Office for the Coordination of Humanitarian Affairs in Syria, at least 166 people were killed in a suicide bombing and other attacks in the southern Syrian province of Suwayda on July 25, 2018. ISIS has taken responsibility.
ISIS claims to have released an audio message from Baghdadi on August 23, 2018. In the 55-minute video, a man admits that ISIS groups are losing and urges his followers to keep fighting.
According to provincial spokesman Attaullah Khogyani, the leader of ISIS in Afghanistan, Abu Sayed Orakzai, and ten other ISIS fighters were killed in an airstrike in Nangarhar province on August 25, 2018.
December 19, 2018 – With a tweet falsely claiming that ISIS has been defeated, US President Donald Trump sets the stage for a rapid withdrawal of American troops from Syria. Although coalition forces have been successful in retaking territory once controlled by ISIS, militants still control a small swath of land near the Euphrates River. Estimates of how many ISIS fighters remain in Syria vary. According to a Defense Department inspector general report, the number of ISIS members in Iraq and Syria could be as high as 30,000.
On January 16, 2019, a deadly explosion in the Syrian city of Manbij kills four Americans and at least ten others. The attack has been claimed by ISIS.
March 23, 2019 – The Syrian Democratic Forces declare that ISIS has lost its last stronghold in Syria, effectively ending the so-called caliphate declared in 2014.
April 2019 – ISIS claims to have released a new video message from Baghdadi for the first time in five years.
The Pentagon issues a report claiming that ISIS is “resurrecting” in Syria on August 6, 2019. Glenn Fine, the principal deputy inspector general, writes in an accompanying message to the report, “The reduction of US forces has decreased the support available for Syrian partner forces at a time when their forces require more training and equipping to respond to the ISIS resurgence.”
October 31, 2019 – ISIS issues an audio message confirming Baghdadi’s death and naming al-Qurashi as its new leader.
January 5, 2020 – The US-led military coalition fighting ISIS announces that it will temporarily suspend counter-ISIS operations to focus on protecting Iraqi bases and coalition forces from Iranian-backed militias.
On July 21, 2020, the US military launches an airstrike against ISIS fighters in Somalia. The fighters had attacked local forces backed by the US and advised by US troops.
In a counterterrorism mission in northwest Syria on February 2, 2022, US Special Forces kill ISIS leader al-Qurayshi.
July 12, 2022 – A drone strike in northwest Syria kills Maher al-Agal, the leader of ISIS in Syria.
On October 6, 2022, US forces assassinate Abu ‘Ala, the deputy leader of ISIS in Syria, and Abu Mu’Ad al-Qahtani, an ISIS official in charge of prisoner affairs. The airstrike comes one day after an ISIS smuggler is killed in a US raid.