Ворскла
In 1395, while Yury was visiting his father-in-law, Oleg Korotopol of Ryazan, Grand Duke Vytautas the Great (Vitovt) of Lithuania took Smolensk and installed his governor there. Four years later, Vytautas was routed by the Tatars in the Battle of the Vorskla River. In 1401, Yury and Oleg made use of his plight to retake Smolensk and Bryansk, where the pro-Lithuanian boyars were promptly executed.