The Islamic State (IS), also known as the Islamic State of Iraq and Syria (ISIS), the Islamic State of Iraq and the Levant (ISIL), or by its Arabic acronym Daesh, is a transnational Salafi-jihadist militant organization. It gained global notoriety for its extreme brutality, territorial conquests in Iraq and Syria, and its 2014 declaration of a worldwide caliphate.
ISIS originated from the chaos and sectarian tensions following the 2003 Iraq War. The group traces its roots to Jama'at al-Tawhid wal-Jihad, established by Abu Musab al-Zarqawi in 1999. In 2004, Zarqawi pledged allegiance to al-Qaeda, forming Al-Qaeda in Iraq (AQI), which became a central actor in the Sunni insurgency against the Iraqi government and foreign forces.
Following Zarqawi's death in 2006, the group merged with other militants and rebranded as the Islamic State of Iraq (ISI). After a period of diminished influence due to opposition from Sunni tribes, the group reorganized under Abu Bakr al-Baghdadi. Capitalizing on the Syrian Civil War and political instability in Iraq, the group expanded into Syria in 2013, eventually breaking away from al-Qaeda. In June 2014, al-Baghdadi declared the establishment of a worldwide caliphate and renamed the organization simply the Islamic State.
The ideology of the Islamic State is rooted in an extremist, puritanical interpretation of Salafism, often described as a hybrid of Salafi-jihadism, Wahhabism, and Qutbism. The group seeks to create a state governed by a strict interpretation of Sharia law, and by proclaiming a worldwide caliphate, claimed religious and political authority over all Muslims globally—a claim rejected by the vast majority of the world's Muslims.
The group infamously utilized effective propaganda strategies, particularly through social media and digital platforms, to recruit members globally and inspire radicalization. A U.S.-led international coalition launched a massive campaign against the group, resulting in the loss of its territorial foothold in Iraq and Syria by late 2017. Although it lost most of its territorial "caliphate," it continues to operate as a decentralized insurgency with various regional affiliates worldwide.