Galicia–Volhynia Wars

Date	1340–1392
Location	Central Europe (today West Ukraine)
Result	Galicia–Volhynia divided between Poland and Lithuania

Belligerents

Kingdom of Poland

local factions

Kingdom of Hungary

Duchy of Masovia

Grand Duchy of Lithuania
Golden Horde

local factions

Commanders and leaders

Casimir III of Poland
Louis I of Hungary
Jogaila

Liubartas
Dmytro Dedko
Vytautas
Tokhtamysh

Galicia–Volhynia Wars were several wars fought in the years 1340–1392 over the succession in the Principality of Galicia–Volhynia (in modern Poland and Ukraine). After Boleslaw-Yuri II was poisoned by local nobles in 1340, both Grand Duchy of Lithuania and Kingdom of Poland advanced claims over the principality. After a prolonged conflict, Galicia–Volhynia was divided between Poland (Galicia) and Lithuania (Volhynia) and the principality ceased to exist as an independent state. Poland acquired a territory of approximately 52,000 square kilometres (20,000 sq mi) with 200,000 inhabitants.

Brothers Andrew and Lev II died ca. 1322, leaving no male successor in Galicia–Volhynia. Instead of promoting his son Liubartas (who was married to Andrew's daughter) and causing a war with Poland, Gediminas of Lithuania compromised with Władysław I of Poland. Both parties agreed to install fourteen-year-old Boleslaw-Yuri II, nephew of Lev and Andrew. Boleslaw-Yuri was a son of Trojden I of Masovia from the Piast dynasty, a cousin of Władysław I and nephew of Gediminas' son-in-law Wenceslaus of Płock. To strengthen the compromise, Boleslaw was betrothed to Eufemija, daughter of Gediminas. Boleslaw was poisoned in April 1340 by local nobles who resented growing Polish and Bohemian influence in the court. Boleslaw did not have an heir and his death upset fragile power balance in the region.

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