Battle of the Alta River
The Battle of Alta River was a 1068 clash on the Alta River between Cuman army on the one hand and Kievan Rus' forces of Grand Prince Iziaslav I of Kiev, Prince Sviatoslav of Chernigov, and Prince Vsevolod of Periaslavl on the other in which the Rus' forces were routed and fled back to Kiev and Chernigov in some disarray. The battle led to an uprising in Kiev that briefly deposed Grand Prince Iziaslav. That incident supposedly shows the power of the Kiev veche and how common people gathering influenced princely politics in Kievan Rus' (particularly in Kiev as well as Novgorod the Great.)