The Town and municipality of Wieluń have a long and extensive history. Archeological findings indicate that the area was settled in 2500 BC. The beginnings of Wieluń are dated on the first half of the 13th century. According to the legend, in 1217 the Władysław Odonic, the Duke of Greater Poland spotted during his hunting of a deer, and upon him the Lamb of God. He founded a settlement in this spot. Its name is derived from the aforementioned deer, and then the name Jeluń was transformed into Wieluń[1.1]. The first record of the town is the a document from 1282 document[1.2]. It is suspected that it was also the date of obtaining the municipality privilege. In the 14th century Kazimierz III Wielki built a castle in Wieluń which was later rebuilt multiple times due to conflagrations. Today in that spot there is a small classicist palace built on on the castle’s foundations.

The town was the capital of the historic Wieluń Land[1.3]. By virtue of the Kazimierz’s last will, Ludwik Węgierski gave the Wieluń Land in 1370 as a liege to Władysław the duke of Opole. Also during that time, Jarosław Bogorya from Skotniki, the archbishop of Gniezno, built a bishop manor in Wieluń. In 1395 Władysław Jagiełło fulfilling the will of the aristocracy once more annexed again Wieluń and Wieluń Land to the Crown. In 1393 he erected a church and the Pauline order monastery in the suburbs. The development of the town entailed the obtainment,obtaining permission to relocate the ancient collegiate church from the village of Ruda to Wieluń by the archbishop Mikołaj Trąba at the general chapter in Gniezno in 1413, of the permission for moving of the ancient collegiate church from the village of Ruda to Wieluń.

In the forties and fifties of the 15th century Wieluń was seriously damaged devestated several times by the Silesian princes. Probably this was a time when the town played an important role as a manufacturing and trading center.

After the death of Zygmunt August, during the interregnum and civil war the town was destroyed. The evidence for that is the privilege of Stefan Batory confirming the privilege of "wójtostwo", which reserved that "utility from this must be used to improve the Town" (Vol. leg., II, § 1014).

In 1588 a famous battle of Byczyna took place nearby Wieluń, where chancellor Jan Zamoyski defeated the army of the archduke Maksymilian Habsburg, the candidate to the Polish crown. After the ceasefire, Wieluń was in pitiful condition. The fortified walls were destroyed and many houses were burnt to the ground.

During the Swedish Deluge the town was devastated further due to struggle fighting between Poles and Swedes. Wieluń was burnt down and the Polish army did unleashed a pogrom upon local Evangelics for favouring the Swedes. Despite the efforts made by the government, it was impossible to revive the past splendour of Wieluń.

The final blow to the town’s development were two cases of pestilence (1707-1711) when approx. 2,000 people died, and the conflagration of 1791. Another disaster caused by the fire took place in 1858.

After this accident the town was rebuilt in and took on a different character. A private mansion was built on the foundations of the former castle. There are still elements of the town walls and the Kraków gate with a high tower have been preserved as well. During the the town’s restoration, a town hall was constructed.

After the second partition of Poland (1793) Wieluń was annexed to Prussia. Between 1807-1815 it was a part of Duchy of Warsaw, and then the Kingdom of Poland. Citizens of Wieluń took part in the January Uprising (1863-1864), 1905 strikes and in the 1919-1921 Silesian Uprisings. The most tragic day of its history was on 1st September 1939 when the helpless, sleeping town was bombed. It was in this place where at 4:40 a.m. the World War II began.