The Battle of the Vorskla River was one of the greatest and bloodiest in the medieval history of Eastern Europe. It was fought on August 12, 1399 between the Tatar hordes of Edigu and Temur Kutlugh and armies of Grand Duke Vytautas of Lithuania.

In the later part of the 14th century, Grand Duke Vytautas and Dmitri Donskoi of Moscow started a rivalry for fertile southern lands, formerly controlled by the Golden Horde. As the Tatar power was on the wane, Dmitriy soundly defeated the Horde at the Snipes' Field (1380), only to be besieged in Moscow several years later by Khan Tokhtamysh.

As a result of the new conflicts within the Horde, Tokhtamysh was dethroned by the party of khan Temur Kutlugh and emir Edigu, supported by the great Tamerlane. When Tokhtamysh asked Vytautas for assistance, the latter readily gathered a huge army which included Lithuanians (Belarusians), Russians, Mongols, Poles, and Teutonic knights. His army met the Tatars at the Vorskla River, a tributary to the Dnieper.

Although Lithuanian army was well equipped with cannons, it couldn't resist a rear attack from Edigu's reserve units. Vytautas could hardly escape alive, many princes of his kin were killed, and the victorious Tatars besieged Kiev. "And the Christian blood have flown like a water, up to the Kievan walls", as one chronicler put it. Meanwhile Temur Kutlugh died from the wounds received in the battle, and Tokhtamysh was killed by one of his own men.

Vytautas' defeat at the Vorskla effectively blocked Lithuanian expansion to Southern Russia. His enormous state also lost hard-won access to the Black Sea. The political activity of Lithuanians was then switched to the fight for northern principalities, such as Smolensk.