The 15th Century
In the end of the Middle Ages (1430-1530) Stege reached its highest point of wealth ever. A third of all fish (Herrings) on the Danish fish market came from fishermen from Møn! That is why Møn's shield contains three herrings.

The fortress however could not stop fire and plague, so a greater part of Stege burned down together with Stege Church's twin-towers, and the plague followed soon after and would take about 30 years to reconstruct the welfare of the town.
In 1447 King Christoffer of Bayern gave Møn the privilege to trade goods outside Møn, but within the borders of Denmark.
In 1450 King Christian the 1st of Denmark forbade the farmers to trade their goods outside Denmark, especially in Germany. The farmers sailed directly to the Germans and sold their goods which contributed to that the merchants in Stege did not get anything to sell and the citizens had nothing to buy.
On 15th of July 1476, King Valdemar's privilege to the town of Stege, regarding the citizens' rights to let their cattle and horses grass in the nearby forests was confirmed by King Christian the 1st. on Stege castle.
In 1481 all foreigners were forbidden to trade with the farmers on Møn, as it hurt the merchants in Stege. All trade should take place in Stege and nowhere else. If any trade were to be discovered anyway, their goods would be confiscated.