Russian army Cossacks have been involved in the war in Syria fighting for the Syrian government since 2013. This was stated by the Ataman (leader) of the Taman division of the Kuban military Cossacks, Ivan Bezugly, in a Youtube video posted by Georgi Kotyonok.
Meduza: Head of Cossack army regiment says Russians have fought in Syria since 2013
Syrian government forces patrol in the village of Khan Tuman on the southern outskirts of the northern embattled city of Aleppo on April 11, 2016 following clashes in the area with opposition fighters the previous night.