The city of Landskrona was founded at the location of Scania's (at that time a part of Denmark) best natural harbour, as a means of King Eric of Pomerania's anti-Hanseatic policy, intended to compete with Danish towns under Hanseatic control. A Carmelite monastery was founded in 1410, English merchants were granted the privileges in a royal charter in 1412, and the town itself was chartered in 1413. Landskrona was burned by the Hanseatic League in 1428.
The foundation was done at a place for a fishing settlement, historical described as S�nder S�by ("s�nder" means "southern"). Still today exists a very small settlement just north of the town, known as S�by (S�by in Danish). This probably was the N�rre S�by ("n�rre" means "northern") in the beginning of the 15:th century, but since the southern village became the town, the need for distinguish northern and southern S�by disappeared. The original name of the officially founded town was Landszkrone. But changed to Landskrone sometime before 1450.
The town supported the king Christian II of Denmark (1525), and opposed the Reformation in Denmark (1535), and in both cases found itself among the defeated. The Reformist King Christian III of Denmark abstained however from retaliation, and instead founded a castle to protect the harbour. The castle, built where the monastery had been situated until the Reformation, was completed by 1560.
When Scania had been ceded to Sweden in 1658, the good harbour and the strong fort were reasons for plans to make Landskrona a commercial center of the acquired territory with extraordinary privileges for foreign trade. The castle was reinforced by bastions, the area inside the moats extended to 400x400 meters, the castle was considered the strongest and most modern in Scandinavia, but was temporarily lost to the Danes after a comparably short siege July 8-August 2, 1676. The commandant Colonel Hieronymus Lindeberg was consequently sentenced to death for high treason
