Muscovite–Lithuanian Wars

The Muscovite–Lithuanian Wars (also known as Russo-Lithuanian Wars, or just either Muscovite Wars or Lithuanian Wars) were a series of wars between the Grand Duchy of Lithuania, allied with the Kingdom of Poland, and the Grand Duchy of Moscow. After several defeats at the hands of Ivan III and Vasily III, the Lithuanians were increasingly reliant on Polish aid, which eventually became an important factor in the creation of the Polish–Lithuanian Commonwealth. Before the first series of wars in the 15th century, the Grand Duchy of Lithuania had already gained control of a lot of Rus' territories, from Kiev to Mozhaisk, following the collapse of Kievan Rus' after the Mongol invasions. Over the course of the series of wars, particularly in the 16th century, the Muscovites were able to expand their domain westwards, taking control of many Rus' lands.

Muscovy and Lithuania had been involved in a series of conflicts since the reign of Gediminas, who defeated a coalition of Ruthenian princes in the Battle on the Irpen' River and seized Kiev, the former capital of Kievan Rus'. By the mid-14th century, an expanding Lithuania had absorbed Chernigov and Severia. Algirdas, the successor of Gediminas, forged an alliance with the Grand Duchy of Tver and undertook three expeditions against Moscow, attempting to take advantage of the youth of the Grand Prince of Moscow, Dmitry Ivanovich, who nevertheless succeeded in fending off these encroachments.

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