Dukat gdański - Jan II Kazimierz Waza Gdańsk mint

Danzig operated under a municipal minting privilege that gave the city's mint considerable autonomy within the Commonwealth, and by 1661 that arrangement was under strain. The Second Northern War had ended only the year prior with the Treaty of Oliva, and Jan II Kazimierz had spent much of the previous decade watching Swedish forces occupy the Polish heartland while Danzig — never taken — became one of the few functioning financial centers in the kingdom.

Kop. 7665 is among the better-documented die marriages for this year's Danzig ducat output, catalogued by Kopicki with enough surviving examples to establish baseline rarity without tipping into genuine scarcity.