The Battle of Klushino is fought between forces of the Polish–Lithuanian Commonwealth and Russia during the Polish–Russian War, after which Polish troops entered Moscow.

The Battle of Klushino, or the Battle of Kłuszyn, was fought on 4 July 1610, between forces of the Polish–Lithuanian Commonwealth and the Tsardom of Russia during the Polish–Russian War, part of Russia's Time of Troubles. The battle occurred near the village of Klushino near Smolensk. In the battle the outnumbered Polish-Lithuanian force secured a decisive victory over Russia, due to the tactical competence of hetman Stanisław Żółkiewski and the military prowess of Polish hussars, the elite of the army of the Crown of the Kingdom of Poland. The battle is remembered as one of the greatest triumphs of the Polish cavalry and an example of excellence and supremacy of the Polish military at the time.

The Polish–Lithuanian Commonwealth, also referred to as Poland–Lithuania or the First Polish Republic, was a federative real union between the Kingdom of Poland and the Grand Duchy of Lithuania, existing from 1569 to 1795. This state was among the largest, most populated countries of 16th- to 18th-century Europe. At its peak in the early 17th century, the Commonwealth spanned approximately 1,000,000 km² (390,000 sq mi) and supported a multi-ethnic population of around 12 million as of 1618. The official languages of the Commonwealth were Polish and Latin, with Catholicism as the state religion.

The Tsardom of Russia, also known as the Tsardom of Moscow, was the centralized Russian state from the assumption of the title of tsar by Ivan IV in 1547 until the foundation of the Russian Empire by Peter the Great in 1721.

The Polish–Russian War was a conflict fought between the Polish–Lithuanian Commonwealth and the Tsardom of Russia from 1609 to 1618.