The Islamic State of Iraq and the Levant (ISIL, IPA: /ˈaɪsɪl/), also known as the Islamic State of Iraq and Syria[note 1] (ISIS /ˈaɪsɪs/),[47] Islamic State (IS), and by its Arabic language acronym Daesh (Arabic: داعش‎‎ dāʿish, Hebrew: דעא"ש, IPA: [ˈdaːʕɪʃ]),[48][49] is a Salafi jihadist militant group and unrecognised proto-state that follows a fundamentalist, Wahhabi doctrine of Sunni Islam.[50][51] ISIL gained global prominence in early 2014 when it drove Iraqi government forces out of key cities in its Western Iraq offensive,[52] followed by its capture of Mosul[53] and the Sinjar massacre.[54]

This group has been designated a terrorist organisation by the United Nations and many individual countries. ISIL is widely known for its videos of beheadings[55] of both soldiers and civilians, including journalists and aid workers, and its destruction of cultural heritage sites.[56] The United Nations holds ISIL responsible for human rights abuses and war crimes, and Amnesty International has charged the group with ethnic cleansing on a "historic scale" in northern Iraq.[57]

ISIL originated as Jama'at al-Tawhid wal-Jihad in 1999, which pledged allegiance to al-Qaeda and participated in the Iraqi insurgency following the 2003 invasion of Iraq by Western forces. The group proclaimed itself a worldwide caliphate[58][59] and began referring to itself as Islamic State (الدولة الإسلامية ad-Dawlah al-Islāmiyah) or IS[60] in June 2014. As a caliphate, it claims religious, political, and military authority over all Muslims worldwide.[61] Its adoption of the name Islamic State and its idea of a caliphate have been widely criticised, with the United Nations, various governments, and mainstream Muslim groups rejecting its statehood.[62]

In Syria, the group conducted ground attacks on both government forces and opposition factions, and by December 2015 it held a large area in western Iraq and eastern Syria containing an estimated 2.8 to 8 million people,[63][64] where it enforced its interpretation of sharia law. ISIL is now believed to be operational in 18 countries across the world, including Afghanistan and Pakistan, with "aspiring branches" in Mali, Egypt, Somalia, Bangladesh, Indonesia, and the Philippines.[65][66][67][68] As of 2015, ISIL was estimated to have an annual budget of more than US$1 billion and a force of more than 30,000 fighters.[69]

In July 2017, the group lost control of its largest city, Mosul, to the Iraqi army.[70] Following this major defeat, in August 2017 ISIL continued to lose territory to the various states and other military forces allied against it, resulting in significant territorial losses for ISIL in the areas of Syria and Iraq.[71]