A Russian army, with the help of…
July 1709 CE
A Russian army, with the help of the Cossack starshyna Halahan (or Galagan), who had disclosed Mazepa's intentions, conducts a preemptive strike and destroys the Zaporizhian Sich on the Dniester, thus denying any possible reinforcements to Swedish troops.
The rest of the Cossacks move their Host down the Dnieper River, where they will remain for the next nineteen years.