What's a Cossack?

i just expect vengeance all the time. Every day is terrible vengeance. The beautiful caterina is married to the cossack master donilo barlbash, and together they have a one year old child. Cossacks dominated ukraine n sixteenth century, but they spent the sixteenth century fighting off invaders. They fought with the polish and the lithuanians, who often were together. And eventually had to turn to the russians for support to try to to oust the poles from ukraine.