During the Middle Ages, an Old Prussian fort called Malcekuke was located near the current site of Pieniężno. The Teutonic Knights built an Ordensburg castle near Malcekuke in 1302. Both the castle and the town which developed nearby were destroyed during the war between the Teutonic Order and the Kingdom of Poland in 1414. During the Thirteen Years' War, Mehlsack surrendered to the Order, and the castle burned down during Poland's recapture of the town. From 1589-1599, Prince Andrew Cardinal Báthory of Transylvania, cousin of Sigismund Báthory, was the administrator for the castle. In 1550, the Prussian army laid siege to the city and partially burned it down.
The town was captured by Swedish troops in 1626 during the Polish-Swedish War of 1625-29, recovered by Hetman Stanisław Rewera Potocki, and then had its castle partially destroyed by Swedish troops in 1627. The castle was restored in 1640 with Baroque gables, and its function changed from being a fortress to being a château.
During the 19th and 20th centuries the castle lost some of its Gothic and Baroque features, and in 1870 its eastern and southern wings were demolished after extensive deterioration. The remainder of the castle was used as administrative offices for Prussianofficials. From 1920-31 the western wing was renovated so the castle could be used as a school and museum. In 1945, Mehlsack, including its castle, was 90% destroyed by fighting during World War II and was conquered by the Soviet Red Army from Nazi Germany.References:
Sirmione castle was built near the end of the 12th century as part of a defensive network surrounding Verona. The castle was maintained and extended first as part of the Veronese protection against their rivals in Milan and later under the control of the Venetian inland empire. The massive fortress is totally surrounded by water and has an inner porch which houses a Roman and Medieval lapidary. From the drawbridge, a staircase leads to the walkways above the walls, providing a marvellous view of the harbour that once sheltered the Scaliger fleet. The doors were fitted with a variety of locking systems, including a drawbridge for horses, carriages and pedestrians, a metal grate and, more recently, double hinged doors. Venice conquered Sirmione in 1405, immediately adopting provisions to render the fortress even more secure, fortifying its outer walls and widening the harbour.
Thanks to its strategical geographical location as a border outpost, Sirmione became a crucial defence and control garrison for the ruling nobles, retaining this function until the 16th century, when its role was taken up by Peschiera del Garda.