The Polish 1st Tadeusz Kościuszko Infantry Division was an infantry division in the Polish armed forces formed in 1943 and named for the Polish and American revolutionary Tadeusz Kościuszko. Formed in the Soviet Union, it was the first division of the First Army, and of what later became the post-war Polish Armed Forces after Invasion of Poland in 1939 and defeating the Nazi Germany in 1945. It was considered part of Polish Armed Forces in the East.

The Battle of Lenino was a tactical World War II engagement that took place on 12 and 13 October 1943, north of the village of Lenino in the Mogilev region of Byelorussia. The battle itself was a part of a larger Soviet Spas-Demensk offensive operation with the aims of clearing the eastern bank of the Dnieper River of German forces and piercing the Panther-Wotan line of defences. The battle is prominent in Polish military history, as it was one of the first major engagements of Polish Armed Forces in the East.