Originating as the Jama'at al-Tawhid wal-Jihad in 1999, it pledged allegiance to al-Qaeda in 2004, participated in the Iraqi insurgency that followed the March 2003 invasion of Iraq by Western forces, joined the fight in the Syrian Civil War beginning in March 2011, and was expelled from al-Qaeda in early 2014, (which complained of its failure to consult and "notorious intransigence"). The group gained prominence after it drove Iraqi government forces out of key cities in western Iraq in a 2014 offensive. The group is adept at social media, posting Internet videos of beheadings of soldiers, civilians, journalists and aid workers, and is known for its destruction of cultural heritage sites. The United Nations has held ISIL responsible for human rights abuses and war crimes, and Amnesty International has reported ethnic cleansing by the group on a "historic scale". The group has been designated a terrorist organisation by the United Nations, the European Union and member states, the United States, India, Indonesia, Turkey, Saudi Arabia, Syria and other countries.
When did ISIL pledge allegiance to al-Qaeda? When did Western forces invade Iraq? Why did al-Qaeda tell ISIL to take a hike? When did the Syrian Civil War begin? What has the United Nations designed ISIL?