Andrei of Polotsk

Andrei of Polotsk (Belarusian: Андрэй Альгердавіч, Lithuanian: Andrius Algirdaitis Polish: Andrzej Olgierdowic, ca. 1325 – 12 August 1399, in the Battle of the Vorskla River) was the eldest son of Algirdas, Grand Duke of Lithuania, and his first wife Maria of Vitebsk. He was Duke of Pskov (through his deputy Yuri, 1342–1348) and Polotsk (1342–1387). As the eldest son of the Grand Duke, Andrei claimed his right to the throne after his father's death in 1377. Algirdas left Jogaila, his eldest son with his second wife Uliana of Tver, as the rightful heir. Andrei's rivalry with Jogaila, Grand Duke of Lithuania and later King of Poland, eventually led to his demise.

In 1342, Andrei joined his father Algirdas and uncle Kęstutis in a war against the Livonian Order to help the Pskov Republic. The Republic asked him to stay as a duke of Pskov so that his presence would guarantee continuous support from Algirdas. Andrei accepted and was baptized in Orthodox rite (his pagan name is unknown). However, he stayed there for a very short time and returned to Lithuania. Reasons are not entirely clear, but historians speculate it was related to death of his great-uncle Vainius, Duke of Polotsk. Polotsk was vital to Lithuanian interests as it was situated between Lithuania and the Livonian Order. Andrei became the Duke of Polotsk and helped defend Lithuania against Livonian attacks. In Pskov, Andrei left his deputy, otherwise unknown Yuri. Lithuanian historian Alvydas Nikžentaitis speculated that this Yuri could have been a grandson of Gediminas.

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