Operation Euphrates Shield was a cross-border military operation conducted by the Turkish Armed Forces in the Syrian Civil War which led to the Turkish occupation of northern Syria. Operations were carried out in the region between the Euphrates river to the east and the rebel-held area around Azaz to the west. The Turkish military and Turkey-aligned Syrian rebel groups, some of which used the Free Syrian Army label, fought against the forces of the Islamic State (IS) as well as against the Syrian Democratic Forces (SDF) from 24 August 2016. On 29 March 2017, the Turkish military officially announced that Operation Euphrates Shield was "successfully completed".

The Syrian Democratic Forces (SDF) is a Kurdish-led coalition formed by ethnic militias and rebel groups, and serves as the official military wing of the Autonomous Administration of North and East Syria (AANES). The SDF is allied to and supplied by the United States–led CJTF–OIR international alliance. Founded in 10 October 2015, the SDF claims that its mission is fighting to create a secular, democratic and federalised Syria. The SDF is opposed by Turkey, who claims the group has direct links to the PKK, which it recognizes as a terrorist group.