The oldest traces of settlers come from the 5th and 6th century. A market town emerged in 1145. In 1370 Inowłódz received town rights. A castle and battlements were built at that time. Inowłódz was an important to the defense of the Kingdom of Poland. In 1655 Czarnecki fought the Swedes near Inowłódz.

After 1795 Inowłódz belonged to Prussia and as of 1807 to the Duchy of Warsaw. In 1815 the town joined Congress Poland.

At the end of the 19th century Inowłódz was a very popular curort, especially for the Jews from Tomaszów, Łódź and Warsaw.

In 1870 Inowłódz lost its town rights.

During World War I, in 1914, the town was on the main front. The fact that during one of the battles fought here the Germans lost 60 thousand soldiers illustrates how seriously Inowłódz was involved in the war. The town was severely damaged.

During the Second World War, in September 1939, German forces invaded the town.