In July 2014, according to the International Institute for Strategic Studies, Iran sent Sukhoi Su-25 aircraft to Iraq, and Hezbollah purportedly sent trainers and advisers to Iraq to monitor ISIL's movements. In August 2014, the US and Iran separately began a campaign of airstrikes on ISIL targets in Iraq. Since then, fourteen countries in a US-led coalition have also executed airstrikes on ISIL in Iraq and in Syria.
In September 2015, Russian forces, with the permission of the Syrian government, began thousands of bombing raids against ISIL, al-Nusra Front, and the Free Syrian Army (FSA).
In the months following the beginning of both air campaigns, ISIL began to lose ground in both Iraq and Syria.Civilian deaths from airstrikes began to mount in 2015 and 2016.[ In mid-2016, the US and Russia planned to begin coordinating their airstrikes; however, this coordination did not materialize.
As of December 2017, ISIL was estimated to control no territory in Iraq, and 5% of Syrian territory, after prolonged actions.On 9 December 2017, Iraq declared victory in the fight against ISIL and stated that the war in Iraq was over. On 23 March 2019, ISIL was completely defeated territorially in Syria after losing the Battle of Baghuz Fawqani