Dmitry Donskoy
Saint Dmitry Ivanovich Donskoy (Russian: Дми́трий Ива́нович Донско́й,also known as Dimitrii), or Dmitry of the Don, sometimes referred to as Dmitry I (12 October 1350, Moscow – 19 May 1389, Moscow), son of Ivan II the Meek of Moscow (1326–1359), reigned as the Prince of Moscow from 1359 and Grand Prince of Vladimir from 1363 to his death. He was the first prince of Moscow to openly challenge Mongol authority in Russia. His nickname, Donskoy (i.e., "of the Don"), alludes to his great victory against the Tatars in the Battle of Kulikovo (1380) which took place on the Don River. He is venerated as a Saint in the Orthodox Church with his feast day on 19 May.
Read more about Dmitry Donskoy: Early Reign, Struggle Against Mamai, Marriage and Children