The Battle of Lyubar or battle of Lubar took place on 14–27 September 1660 near Lyubar, during the Russo-Polish War (1654–1667), between the forces of the Polish–Lithuanian Commonwealth (allied with the Tatars) and Tsardom of Russia (allied with the Cossacks). It was the first battle of the 1660 campaign in the south. It ended with a Polish victory. The Russian army retreated and was subsequently destroyed during the battle of Chudniv. Background In July 1660, Tsar Alexis I of Russia ordered Vasily Sheremetev to resume the sporadic Russo-Polish War (1654–1667) and push the Poles west, taking Lviv and securing disputed Ukrainian territories for Russia. In September 1660, the commander of the Russian army, Sheremetev, acting on misleading information that greatly underestimated the numerical strength of the Polish army decided to seek out and destroy the Polish forces with what he believed would be overwhelming strength (15,000 Russian soldiers and 15,000–35,000 of his Cossack allies). Sheremetev's major tactical error was to advance relying on outdated and sparse intelligence reports, and without adequate scouting. He expected only a weak army of 10,000 (in fact, it numbered only about 7,000) under Great Crown Hetman Stanisław "Rewera" Potocki and was unaware it was soon to be reinforced by about 12,000 men under Field Crown Hetman Jerzy Sebastian Lubomirski who recently defeated a Russian army in Lithuania. The Polish commanders Hetmans Potocki and Lubomirski had much better intelligence (they were also aided by Ivan Vyhovsky spy network) and quickly became aware of Sheremetev's error. Polish historian Łossowski notes that "while Sheremetev's advanced blindly, the Polish hetmans knew almost everything about his army and moves". They decided to engage his forces before he could be reinforced by his Cossack allies. Part of the Cossacks (about 15,000 under Timofey Tsetsura (Pol: Tymofiej Cieciura)) were to stay with Sheremetev's corps, and another part (about 20,000 under Yurii Khmelnytsky), according to Sheremetev's plan were to intercept and defeat the 12,000 strong Tatars from the Crimean Khanate under nuradyn-sultan Safer Giray (of whose coming to Polish aid Sheremetev was aware). However, Khmelnytsky failed to stop the Tatars and most of the Tatar forces slipped past him around middle of August. Further, the Cossack's leader, Yurii Khmelnytsky, was increasingly at odds with Sheremetev (who favored Tsetsura over Khmelnytsky, and who refused to promise Khmelnytsky any loot from the upcoming battles), and was in no hurry to execute Sheremetev's orders or stick