The history of the town dates back to the early years of Polish statehood. Mentioned as Uneievo in a bull of
Pope Innocent II (1136), Uniejów is one of the oldest towns of Poland. At that time it belonged to the
Archbishops of Gniezno, and received its town charter most likely before 1290. The first Archbishop residing mainly in Uniejów in the city was
Bogumilus in the 12th century. In the late 13th century, Archbishop
Jakub Świnka founded Church of the Holy Spirit and a hospital, and in 1331, Uniejów was burned by the
Teutonic Knights. Like many Polish cities, Uniejów declined after the mid-17th century
Swedish invasion of Poland. The castle was ransacked, and the town itself was burned. There also were two dangerous fires, in 1736 and 1790, and after the
Congress of Vienna (1815), the town became part of
Russian-controlled
Congress Poland, where it remained until
World War I. In 1836, Uniejów was granted to a Tsarist General
Karl Wilhelm von Toll. During the
January Uprising, it was the site of a battle between Polish insurgents and Russian troops on October 12, 1863. As punishment for the unsuccessful uprising, Uniejów was one of many towns stripped of its town charter in 1870. In 1919 Uniejów again became a town after Poland regained independence in 1918. In September 1939, during the German
invasion of Poland, which started
World War II, Polish units of
Poznań Army resisted here the advancing
Wehrmacht. During the heavy fighting, Uniejów was partially burned. In revenge for the Polish defense, the Germans carried out two massacres of Polish inhabitants, killing 36 and 14 people respectively on September 6 and 8. The
Jewish population of Uniejów, numbering slightly over 1,000 was immediately brutalized by the invaders, kidnapped for forced labor, beaten, and robbed. In 1940, they were moved into a
ghetto in the more decrepit part of town and the following year, the entire Jewish population of around 500 was forced to live in four buildings. Some able bodied men were sent to work camps near
Poznań. In April 1940, the Germans arrested local Polish teachers. The local school principal and teachers were among Polish teachers murdered in the
Mauthausen concentration camp. In June 1940, the Germans
expelled 88 Poles, whose homes were handed over to
German colonists as part of the
Lebensraum policy. In October 1941, all the community's Jewish population was sent to a ghetto in
Kowale Pańskie where in July 1942 most were sent to the
Chełmno extermination camp where they were immediately gassed. A few were sent to the
Łódź Ghetto. There were few survivors among Uniejów's Jewish population, perhaps around 20. Men of the nationalist Polish underground murdered one survivor in the Turek Forest in late 1945, months after the war ended. Currently, Uniejów is a spa and tourist destination, due to its landscape park and geothermal waters. The town has several restaurants, hotel located in the castle, and other amenities. There also are walking and bicycle trails. Among sights are Gothic castle (built in 1360-1365 by Archbishop
Jaroslaw of Bogoria and Skotnik, restored in 1956–67), collegiate with a 14th-century Gothic presbytery, neo-Baroque church tower (1901), Classicistic manor house (1845). The village of
Spycimierz, with its ancient Slavic
gord, lies away. == Thermal spa ==