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Islamic State of Iraq and ash-Sham (ISIS)



ISIS flag

ISIS is a Salafi-jihadist group that has conducted and inspired terrorist attacks worldwide, resulting in thousands killed or injured. In 2004, an Iraqi extremist network led by Abu Musab al-Zarqawi merged with al-Qa‘ida to form ISIS’s predecessor group, al-Qa‘ida in Iraq (AQI), which Zarqawi led until his death in 2006. Now-deceased amir Abu Bakr al-Baghdadi took over the group in 2010 and began to expand its operations into eastern Syria in 2011. In 2013, AQI changed its name to ISIS; and in 2014, the group separated from al-Qa‘ida, declared itself a caliphate, and took over vast swaths of territory in Iraq and Syria.

In 2019, an international coalition ejected ISIS from its last stronghold in Syria, although the group continues to operate clandestinely there and in Iraq. Despite losing many of its leaders and its territory, ISIS remains capable of conducting insurgent operations in Iraq and Syria while overseeing at least 19 branches and networks in Africa, Asia, and Europe. Some of ISIS’s most prominent branches and networks are detailed in separate entries on this site.

Based primarily in northern and eastern Syria and northern Iraq

Approximately 8,000-16,000 in Iraq and Syria

ISIS uses targeted killings, IED attacks, ambushes, military-style assaults, kidnappings, and suicide attacks in Iraq and Syria. The group also encourages adherents worldwide to conduct operations in their own countries using readily available weapons, and it has previously deployed operatives abroad to execute attacks. ISIS mostly attacks military targets and civilian defense forces in Iraq and Syria. The group also frequently targets government personnel and infrastructure, in addition to foreign aid workers and civilians who ISIS perceives are working against it or are opposed to its interpretation of Islamic law.

The US State Department designated AQI, ISIS’s predecessor, as a foreign terrorist organization in December 2004—a designation that remains in effect for ISIS. Several ISIS leaders have also been named Specially Designated Global Terrorists, including former leaders Hajji ‘Abdallah in 2020, Abu Bakr al-Baghdadi in 2011, and Abu Musab al-Zarqawi in 2003.


Abu photo

Abu al-Hassan al-Hashimi al-Qurayshi
ISIS overall amir who succeeded Hajji ‘Abdallah in February 2022

Amir photo

Amir Muhammad Said Abdal-Rahman al-Mawla  [DECEASED]
a.k.a. Hajji ‘Abdallah
Deceased former amir who succeeded al-Baghdadi in October 2019; previously served as deputy amir; was an active member of AQI

Ibrahim photo

Ibrahim Awwad Ibrahim Ali al-Badri  [DECEASED]
a.k.a. Abu Bakr al-Baghdadi
Deceased former amir who assumed control of the group in 2010 and declared himself caliph in 2014; killed by US forces in Syria in October 2019

Abu Musab photo

Abu Musab al-Zarqawi  [DECEASED]
Deceased founder and amir of AQI from 2004 until his death in 2006; killed by a US airstrike in Iraq


20 January 2022

Hasakah, Syria

ISIS attacks Ghuwaryan prison (a.k.a PRISF Hasakah) leading to a weeklong siege on the facility and surrounding neighborhoods, killing more than 100 prison guards and 400 ISIS detainees.

19 July 2021

Baghdad, Iraq

ISIS conducts a suicide bombing in a crowded market on the eve of the Eid al-Adha holiday, killing at least 35 people and injuring more than 60 others.

16 January 2019

Manbij, Syria

ISIS conducts a suicide bombing outside a restaurant, killing 15 people—including four Americans.

3 July 2016

Baghdad, Iraq

ISIS carries out a suicide car-bombing that kills more than 200 people.

26 June 2015

Kobane, Syria

ISIS fighters assault the town, killing at least 145 civilians.

May 2015

Ramadi, Iraq

ISIS fighters take control of Ramadi, the largest city in western Iraq, holding it until December 2015.