I think you are wrong .Cossacks is from the word Kasog ,which was Rus term for Circassian. Many towns of Eastern Ukraine had Circassian names as many circassian and chechen tribes were invited by tsars (on the condition they convert) to parts of ukraine that Russia captured from Crimean tatars,nogais in Kuban . Even before mongol invasion ,kievan rus who invite circassians to come and settle on their lands as slavic people have historical tendency to laziness ,though they are good warriors.
Although Cossacks lived in the region prior to the late 18th century
[1] (one theory of Cossack origin traces their lineage to the ancient Kasog peoples who populated the Kuban in 9th-13th centuries
Nomads in the Sedentary World - Anatoly M. Khazanov, Andre Wink - Google Books
The first Cossacks on the Kuban (1444-1716)
It thought that the term Cossack originated in the Kuban, from the ancient Circassian
Kassak (alternative version
kasog) where it entered the Turkic language and from there was adopted by the latter proto-Cossack groups of the Don and Dnieper.
Home - WW2 Soviet Guards
According to some historians ,Cossacks are descendants of Kasog Circassians and Scythian slav who merged into a common people.Plus a lot of people were imported from caucusus to improve russian agricultural output .
UKRAINIAN NAMES.
Closing-KO has Adygeyan language meaning "son" (ko), that is formed in Ukraine last name exactly as in Russia, but in Russia, "the son of Peter," and the son fell off was just Petrov (as well as itself in Bulgaria and the Czech Republic and Slovakia), in Ukraine said whose son Peter's son, ie PETRO-KO (by adygskie son of Peter), etc., the same Turkic roots have surnames on-UK,-CC, (Turkic Gayuk, Tayuk, Kucuk) Ukrainian Kravchuk Mykolaychuk and so on.
In addition a number of Ukrainian surnames were absolutely Turkic Buchma Kuchma (the Turkic language is a high peaked cap)!
Such a common Ukrainian surname as Shevchenko has Circassian origin, had this name just at the time when the Dnieper Cherkasov appeared Kasogs and Circassian tribes (hence the Cherkassy). It goes back to the word "sheudzhen" which Circassians designated their Christian priests. Under the onslaught of Islam Sheudzhen emigrated from the Ukraine part of Circassian. Their descendants naturally called "shevdzhenko", "Shevchenko", it is known that adygskie "KO" is a descendant of the son. Another very common surname Shevchuk back to adygskoj name Shevtsuk. Mazeppa - Circassian family name, in the same form Some people in the Caucasus.
