(in Polish, Witold Olgier-dowicz). Born 1325; died 1399. Son of Olgerd, grand duke of Lithuania.
In 1341, Andreas Ol’gerdovich was baptized and invited, by agreement with Olgerd, to become prince of Pskov. Soon afterward Olgerd made his son prince of Polotsk, while retaining Pskov for Ol’gerdovich. Andreas moved to Polotsk and ruled Pskov through a representative until 1348. In 1373 and 1375 he took part in campaigns against the Livonian Order. After Olgerd’s death in 1377, Ol’gerdovich was defeated in his fight for the Lithuanian grand ducal throne and fled to Pskov, where he became prince once more with the consent of Dmitrii, grand duke of Muscovy. In 1379 he joined the Russian princes in the campaign against Lithuania, and in 1380 he joined them in the battle of Kulikov. Later he became prince of Polotsk once more. In 1386 he undertook a second fight for the Lithuanian grand ducal throne but was again defeated and captured. In 1393 he fled from captivity, arrived in Pskov, and for the third time became prince of Pskov. Soon, however, he entered the service of Witowt. He died in a battle with the Tatars near the river Vorskla.