After the death of its ruler Berdi Beg Khan in 1359 the Golden Horde experienced a series of succession disputes and wars that lasted two decades (1359–81). The Horde began fracturing into separate districts (ulus). Taking advantage of internal disorder within the Horde, Grand Duke Algirdas of Lithuania organized a campaign into Tatar lands. He aimed to secure and expand southern territories of the Grand Duchy of Lithuania, particularly the Principality of Kiev. Kiev had already come under semi-Lithuanian control after the Battle on the Irpin River in early 1320s, but still paid tribute to the Horde.

The Battle of Blue Waters was a battle fought at some time in autumn 1362 or 1363 on the banks of the Syniukha river, left tributary of the Southern Bug, between the armies of the Grand Duchy of Lithuania and the Golden Horde. The Lithuanians won a decisive victory and finalized their conquest of the Principality of Kiev.

The victory brought Kyiv and a large part of present-day Ukraine, including sparsely populated Podolia and Dykra, under the control of the expanding Grand Duchy of Lithuania. Lithuania also gained access to the Black Sea. Algirdas left his son Vladimir in Kyiv. After taking Kyiv, Lithuania became a direct neighbor and rival of the Grand Duchy of Moscow.