Oleg Yaroslavich

Oleg Yaroslavich "Nastasich" (after 1161 – 1189) was Prince of Galicia (1187; 1189).

Life
Oleg was the illegitimate son of Prince Yaroslav Osmomysl by his mistress, Nastaska, a daughter of a local boyar. The Galician boyars had his mother burned as a witch, forced his father to reinstate his wife (whom Yaroslav had left in order to take Oleg’s mother), and imprisoned Oleg.

Yaroslav died on 1 October 1187, giving Peremyshl (Przemyśl) to his only legitimate son, Vladimir Yaroslavich. At the same time, he designated Oleg as his successor in Halych, requesting that Vladimir and the Galicians promise not to take the city from Oleg. After his death, however, Oleg was deposed and had to seek help from Rurik Rostislavich in Vruchiy. After Oleg failed to solicit aid from Ryurik Rostislavich, he went to Duke Casimir II of Poland (1177–1194).

Oleg's stepbrother, Vladimir Yaroslavych lived a dissolute life and took to himself a priest's wife. When the Galician boyars threatened to kill his wife, Vladimir Yaroslavich took her and his two sons and fled to King Béla III of Hungary (1172–1196). A later chronicle, however, describes the event differently, stating that Oleg and Duke Casimir II defeated Vladimir Yaroslavich and forced him to flee to the Hungarians, after which Casimir II appointed Oleg to Halych.

Oleg was poisoned by the townspeople of Galicia who invited Roman Mstislavich to be their prince.