Demetrius I Starshy

Dmitry I Starshy or Dmitry of Bryansk (Lithuanian: Dmitrijus Algirdaitis, died on 12 August 1399 in the Battle of the Vorskla River) was the second eldest son of Algirdas, Grand Duke of Lithuania, and his first wife Maria of Vitebsk. He was Duke of Bryansk from 1356 to 1379 and from 1388 to 1399.

In 1356 Algirdas took region of Bryansk, which included Trubetsk and Starodub, from Principality of Smolensk and granted to his son Dmitry to govern it. The territory was in far north east from the heartlands of the Grand Duchy of Lithuania and bordered the Grand Duchy of Moscow. In 1370 Dmitri Donskoi, Grand Duke of Moscow, unsuccessfully attempted to conquer the territory. In 1372 Dmitry witnessed Treaty of Lyubutsk between Algirdas and Dmitri Donskoi.

After his father's death in 1377 Dmitry supported his elder brother Andrei of Polotsk against their younger half-brother Jogaila, who became the Grand Duke of Lithuania. Andrei, believing that he is the rightful heir to the throne, organized an anti-Lithuanian coalition, which included Polotsk, Pskov, Livonian Order, and Grand Duchy of Moscow. Dmitry took a more passive role in the coalition: he did not wage a direct war against Lithuania and did not defend his domain when it was attacked by Moscow's army in 1379. Dmitry and his family followed retreating Russian army into Moscow where Dmitri Donskoi granted him Pereslavl-Zalessky. In 1380 Dmitry led a Russian banner in the Battle of Kulikovo against the Golden Horde. Russian chronicles praise his and his brother's tactical skills.

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