The Islamic State (IS) grew out of al-Qaeda in Iraq in the 2000s, declaring a caliphate in 2014 across Iraq and Syria. Led by Abu Bakr al-Baghdadi, IS seized territory through military offensives and governed via Sharia law, notable for extreme brutality. IS established an economy from oil/gas, taxation, antiquities trafficking and slavery to become financially self-sufficient. An international coalition conducted airstrikes against IS while local forces retook cities like Ramadi and Mosul. Al-Baghdadi was killed in 2019 but IS affiliates remain active as imprisoned fighters may radicalize others in the future.