Global Terrorism Index 2025

​Results
 
Islamic State and Affiliates: Islamic State of Iraq and the Levant
The emergence of Islamic State in Iraq and the Levant (ISIL), also known as Islamic State of Iraq and Syria (ISIS) can be traced back to the mid-2000s, when the group initially formed as al-Qaeda in Iraq (AQI). AQI was established by Abu Musab al-Zarqawi in 2004, shortly after the US invasion of Iraq. The group capitalised on the instability and sectarian violence in Iraq, positioning itself as a major player in the insurgency. 
 
By 2006, the group expanded its operations and changed its name to the Islamic State of Iraq (ISI), signalling its growing ambition to create an Islamic state. The group’s leadership, under Abu Bakr al-Baghdadi after Zarqawi's death in 2006, focused on establishing a territorial base in northern Iraq. Over the next few years, ISI claimed many terrorist attacks inside Iraq, including the attacks in Baghdad in August, October and December 2009, which, combined, killed over 480 people.However, ISI faced significant challenges due to limited resources and internal conflicts, while the Iraqi government and US forces mounted a strong resistance against its advances. 
 
Facing backlash from the community and increased pressure from US and Iraqi forces, the group weakened until 2011, when its involvement in the Syrian Civil War sparked a period of renewed growth. In 2013, under Baghdadi’s leadership, the group rebranded itself as Islamic State in Iraq and the Levant (ISIL). In 2014, it formally broke ties with Al-Qaeda.
 
ISIL exploited the power vacuum in Syria to expand its influence into neighbouring areas, engaging in conflicts with tribal groups and militias in Iraq, and against Kurdish forces and various rebel factions in Syria. Strengthened by an influx of fighters from across the region, the group rapidly evolved, marking the early stages of its transformation into a global extremist organisation. 
 
In June 2014, ISIL captured Mosul and again changed its name to Islamic State (IS), declaring a caliphate and naming its leader, Abu Bakr al-Baghdadi, the “Caliph.” This declaration marked a significant turning point for the group, as it now claimed religious and political authority. The caliphate’s territory spanned parts of Iraq and Syria, totalling an area roughly the size of France at its peak. IS sought to implement a strict interpretation of Islamic law in the areas it controlled. 
 
In September 2014, the United States and a coalition of allies launched airstrikes against IS positions, while local forces, including the Iraqi military and Kurdish fighters, mounted a resistance against the group’s expansion. Despite the setbacks, IS continued to hold significant territory and maintained its control over large swathes of land in both Iraq and Syria for much of 2014 and 2015. In 2015, the group established a presence in Libya.
 
Terrorism deaths attributed to IS peaked in 2016 at 4,240 reported fatalities. While the death toll has fluctuated over the years, it has generally declined since its peak, reaching 1,805 in 2024. Despite this reduction, IS remains a significant threat, as ongoing casualties in recent years demonstrate. Up until 2016, most IS deaths were concentrated in Syria and Iraq. However, since then, fatalities in other regions have increased, highlighting the expanding reach and influence of IS affiliates across different parts of the world. 
 
The decline of IS began in 2016 as military efforts to reestablish Syrian and Iraqi governmental control of the countries’ territories gained momentum. In Iraq, the Iraqi military, supported by a US-led coalition, launched a series of offensives to retake key cities, culminating in the reclaiming of Mosul in 2017, a decisive turning point in the fight against IS. Similarly, in Syria, Syrian Democratic Forces (SDF), supported by the US, made significant advances, gradually pushing IS out of its strongholds, including Raqqa, which fell in 2017. By 2019, IS had lost most of its territory, and the group’s self-declared caliphate was effectively dismantled. 
 
Despite losing its territorial holdings, IS remained a significant threat through its insurgency activities, continuing to carry out attacks in Iraq, Syria and beyond. The group’s leadership adapted by going underground or fleeing to other regions, including parts of Africa and Southeast Asia. The decline of IS’s geographical caliphate did not mark its end; instead, the group transitioned to a more decentralised model, relying on cells and affiliates to sustain its violent campaign and spread its ideology. 
 
IS maintains a presence in northeastern Syria and parts of Iraq, while its regional affiliates, including IS-Sahel, ISWA and ISK, have gained increasing prominence. Since the end of IS’s territorial holdings in Iraq and Syria, attacks previously attributed to ISIL are now attributed to IS. The other regional branches of IS, such as ISWA, have seen a rise in activity in recent years, with the number of attacks increasing from two increases, with their attack numbers rising from a few incidents in 2015 to larger spikes in recent years, such as 189 attacks in 2021. This underscores both the persistence of the IS network and the shifting geography of its operations. 
 
Different IS provinces have adapted their strategies to suit their local contexts. IS-Sahel, for example, has focused on capturing and holding territory, while ISK has pursued a more transnational agenda. The internal dynamics of these provinces, along with the conflict environments in which they operate, have shaped their divergent approaches, making IS difficult to define. 
 
Global Terrorism Index 2025. Institute for Economics & Peace. Sydney, Australia.