[1] The oldest known mention of Ślesin comes from a document of Polish monarch Konrad I of Masovia from 1231.

After the successful Greater Poland uprising of 1806, it was regained by Poles and included within the short-lived Duchy of Warsaw.

Battles of the January Uprising between Polish insurgents and Russian troops were fought near Ślesin on March 22 and October 10, 1863.

During World War II, Ślesin was occupied by the Wehrmacht on 13 September 1939, annexed to Nazi Germany from 1939 to 1945 and administered as part of the newly formed province of Reichsgau Wartheland.

The town was liberated by the Red Army on 20 January 1945 during the Vistula–Oder Offensive, and restored to Poland.