Dmitri Donskoi
Ivan's successors continued gathering the lands of Rus' to increase the population and wealth under their rule. In the process, their interests clashed with the expanding Grand Duchy of Lithuania, whose subjects were predominantly East Slavic and Orthodox. Grand Duke Algirdas of Lithuania allied himself by marriage with Tver and undertook three expeditions against Moscow (1368, 1370, 1372) but was unable to take it. The main bone of contention between Moscow and Vilnius was the large city of Smolensk.
In the 1350s, the country and the royal family were hit by the Black Death. Dmitry Ivanovich was aged nine, when his parents died and the title of Grand Duke slipped into the hands of his distant relative, Dmitry of Suzdal. Surrounded by Lithuanians and Muslim nomads, the ruler of Moscow cultivated an alliance with the Rus' Orthodox Church, which experienced a resurgence in influence, due to the monastic reform of St. Sergius of Radonezh.
Educated by Metropolitan Alexis, Dmitri posed as a champion of Orthodoxy and managed to unite the warring principalities of Rus' in his struggle against the Horde. He challenged the Khan's authority and defeated his commander Mamai in the epic Battle of Kulikovo (1380). However, the victory did not bring any short-term benefits; Tokhtamysh in 1382, sacked Moscow hoping to reassert his vested authority over his vassal, the Grand Prince, and his own Mongol hegemony, killing 24,000 people.
Nevertheless, Dmitri became a national hero. The memory of Kulikovo Pole made the Rus' population start believing in their ability to end Tatar domination and become a free people. Dmitri successfully overcame the stigma of collaborating with the Tatars which had been attached to Moscow for decades. In 1389, he passed the throne to his son Vasily I without bothering to obtain the Khan's sanction.
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