Battle of the Vikhra River

Andrei of Polotsk fought with his younger half-brother Jogaila for the throne of the Grand Duchy of Lithuania. Andrei allied with the Livonian Order and Prince Sviatoslav II of Smolensk [ru], who wanted to reconquer the Principality of Mstislavl.^[3] In February 1386, when Jogaila and his allies celebrated his wedding to Jadwiga of Poland and coronation as Polish king in Kraków, the Order invaded Lithuania, almost reaching Vilnius. In March, the army of Smolensk besieged Vitebsk and Orsha, but could not take them.^[3] Sviatoslav devastated many lands on the Lithuanian border and besieged Mstislavl, which was defended by Karigaila, son of Algirdas.^[4]

Upon hearing the news of the invasion, Jogaila sent a great army under the command of his brother Skirgaila.^[3] The army also included Kaributas, Lengvenis, and Vytautas. Mstislavl withstood ten days of siege before the Lithuanian army reached it and engaged the Smolensk army.^[5] The result of the battle was a complete defeat of the Smolensk troops and the deaths of Sviatoslav and his nephew Ivan.^[2] Two of Sviatoslav's sons, Gleb and Yury, were seriously wounded and taken prisoners. Skirgaila's army approached Smolensk, but did not lay siege. Yury, who according to the Bychowiec Chronicle was married to a niece of Skirgaila and Jogaila, was installed as the prince of Smolensk and as a vassal to Lithuania.^[6] Gleb Sviatoslavich was taken as a hostage to Lithuania.

Eventually, Gleb returned to Smolensk and challenged Yury for the throne. This provided Grand Duke Vytautas with an opportunity to seize Smolensk in 1395.^[7]