Сигизмунд Кейстутович
Švitrigaila with several thousand troops (estimated to total about 40,000) marched out of Polatsk, where he was staying, and took Minsk, Kreva, Ashmiany, and was preparing to attack Vilnius. Sigismund Kęstutaitis' Lithuanian and Samogitian army supported by Masurians from Drahichyn (estimated to total about 20,000) attacked Švitrigaila's Lithuanian and Russian troops supported by Tatars, led by Khan Sayid Ahmad I. Švitrigaila's Livonian Order allies did not arrive in time for the battle.