Algirdas(redirected from Olgierd)
(also Olgerd), grand duke of Lithuania from 1345 to 1377. Son of Gediminas.
In alliance with his brother Ke̢stutis, Algirdas conducted a resolute and successful campaign to expand the territory of the Grand Duchy of Lithuania. He fought battles on the Stréva River west of Trakai (1348) and at Rudava (1370), in which the Teutonic Order’s forces were defeated. In 1363 he defeated a Mongol Tatar army at Sinie Vody. Algirdas seized several Cher-nigov-Severskii appanages, the Kievan Land, Podolia, and Volyn’ and annexed the Principality of Smolensk to Lithuania. Without notable success he also attempted to extend his influence to Pskov and Novgorod. Algirdas failed in his attempt to conclude an anti-Moscow alliance with Khan Dzhanibek in 1349. Between 1368 and 1372, he supported Tver’ against Moscow and unsuccessfully attacked Moscow three times, in 1368, 1370, and 1372.
REFERENCEGrekov, I. B. Ocherki po istorii mezhdunarodnykh otnoshenii Vostochnoi Ewopy XIV-XVI vv. Moscow, 1963.
S. M. KASHTANOV