While the ISIS caliphate, which covered a swath of land across Iraq and Syria the size of Great Britain, was declared officially defeated in March of 2019, it had lost significant territory — as well as subjects, fighters, and sources of income — by 2018.
Its swift and brutal rise in 2014 put ISIS at the top of the GTI's list of deadliest terror groups from 2014 through 2017.
Last year, the GTI reports, ISIS was responsible for 1,328 deaths around the world, a 69% decrease from 2017, and an 85% decrease from 2016. ISIS's deadliest attacks occurred in Syria, including one in Deir Ezzor, Syria, which involved 10 suicide bombers and four vehicle-borne improvised explosive devices (VBIEDS) and killed at least 51.
Although GTI counts the terror group's affiliate, the Islamic State Khorasan chapter (ISIS-K), as a separate terror enterprise, the group has pledged its allegiance to the global ISIS enterprise, which has moved fighters to Afghanistan to stage attacks from there.
According to GTI, ISIS-K's fighting force has declined to about 600 to 800 from a peak of about 3,000 to 4,000 in 2016. The number of attacks they've staged have decreased as well — but they've become deadlier, as 2018 marked the highest number of deaths from ISIS-K attacks since the group's formation in 2014.
Last year, ISIS-K was responsible for 1,060 deaths — most of them in Afghanistan.