Russia 3e Cossacks

[Kromm]

Knowing people from actual Cossack families, I'd stay that the definitive trait of real-world Cossacks was mostly "Doesn't want to be ruled but is willing to work for a ruler who has no designs on ruling them." That's really it.

The entire idea that the Cossacks were raging land-pirates on horseback is essentially really good Russian propaganda, though not without basis in reality (keep reading). They were mostly people who declared themselves beyond the Tsar's rule, went off and lived semi-nomadically in places where the Tsar didn't have or particularly want much reach, and then took the Tsar's offers of honors, money, and land to fight on the Tsar's side ("for the Tsar" would be a reach) against people who concerned the Tsar more than a gang of militarized wanderers in the frontier regions; e.g., the Ottomans. The Cossack tendency to run down stragglers and loot as payment for service was the basis of the "raging land-pirate" thing, but it was mostly done in military service.

Even the "on horseback" bit is exaggerated. That's the Don Cossacks. It's true that they were the most famous military subgroup, but the vast majority of Cossacks who were just off living life didn't ride around on horses (which were expensive and mostly sustainable only by Tsar-paid Don cavalry), and not military but militarized, fighting as infantry when pressed. They actually had quite a reputation as snipers, and were Russia's answer to the classic "natives who know the land better than you and come out of the bushes at night to ambush you in close quarters" meme.