Collegiate church of the Assumption of the Virgin Mary in Uniejów was founded in 1349. Its founder was archbishop Jarosław Bogoria Skotnicki. In 1939, during the war, the collegiate church suffered severe damage. In the years 1945-1946 the temple was rebuilt.
The church is built in gothic style with bricks of polish layout. It is a one-nave building with a separate narrower presbytery. The original rib vaulted ceiling of the 14th century is preserved.