The Free City of Danzig was an independent city state between 1807 and 1815 and again from 1920 until 1939. Located at the Baltic Sea in Pomerania, in the north of present-day Poland, it was hotly contested between Germans and Polish over the course of history. The Polish name for the city is Gdansk, but because during times the Free City existed (and when it had its own coinage) the majority of the population spoke German, the name Danzig is used in the Numista catalogue.
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