The Second Karabakh War (September 27 – November 9, 2020) was the latest escalation of an unresolved conflict over the region, which is internationally recognized as part of Azerbaijan, but partially governed by the Republic of Artsakh, a breakaway state with an Armenian ethnic majority. As a result of the war, territories surrounding Nagorno-Karabakh including Jabrayil, Fuzuli, Qubadli and Zangilan as well as a strategic town of Shusha (to Azerbaijanis and Shushi to Armenians) were returned under Azerbaijani control. After six weeks of fierce fighting, Armenia and Azerbaijan agreed to end military operations in and around Nagorno-Karabakh in a ceasefire. Following the violent escalation of conflict in Nagorno-Karabakh, the region has witnessed the various (and sometimes contradictory) widespread rumours of foreign fighters and volunteers including members of the Syria Free Army and Syrian Turkmens ostensibly having been imported to the Karabakh conflict. Reputable international media organizations, foreign governments, and independent analysts are not the only sources who report Syrian mercenaries have been fighting for Azerbaijan. There also are videos circulating on social media that purportedly show Syrian fighters in the conflict. The participation of foreign fighters in the Karabakh war is not new. From 1992 to 1994, thousands of foreign fighters mostly Chechens and Afghan mujahideen were fighting on the side of Azerbaijan in the first Nagorno- Karabakh war. Members of the Armenian diaspora have travelled to the South Caucasus, answering the call of Yerevan to defend the disputed land. However, engagement of foreign fighters in The Second Karabakh War (September 27 – November 9, 2020) is very important, because the conflict escalated into a full-scale war and led to withdraw of Armenian troops from seven territories around Nagorno-Karabakh as well as a strategic town of Shusha. The rivalry between Turkey and Russia in Syria and Libya was another important factor. Turkey sent between 3.500 and 3.800 paid Syrian fighters to Libya in 2019 to fight on the side of the UN-supported government, which was likely to degrade security and generate backlash from the Libyan public. Therefore some experts believe that the 2020 Nagorno-Karabakh War was “third front of rivalry” between Turkey and Russia and the presence of foreign fighters in the war can be evaluated in this context. Indeed, Ankara and Baku accused Armenia of transferring People’s Protection Units (YPG) and the Kurdistan Workers’ Party (PKK) fighters from Syria and Iraq to the occupied Nagorno-Karabakh to train militias. The sum of these issues made this a challenging issue in the 2020 Nagorno-Karabakh War.