Here's a little background on the state of affairs in Poland before WWII. In 1795, Poland was completely partitioned among the Kingdom of Prussia (Germany), Russia, and Austria. From 1795 until the end of WWI and the Treaty of Versailles, Poland did not exist. The Treaty of Versailles created the Second Polish Republic in 1918.

Another term from the Treaty of Versailles was to establish Danzig (Gdansk, which had been in Germany during the century of Polish non-existence) as a Free City. [My understanding is that this was done to allow more countries than just Germany access to the Baltic Sea and shipping. I could be wrong, it’s happened twice before.] Under the regulations of this free city, Poland would represent the Free City of Danzig in international affairs, Poland would be able to establish a base for military transport at the port, and Poland would have a Post Office within the city for servicing Polish mail and telegraph needs.

At the time (roughly 1920s) Danzig was 90% German-heritage and 10% Polish. It was not a comfortable co-habitation. The Germans considered Poles inferior, and they were vocal about this belief.

During the 1920s and early 1930s, as the Nazis were gaining strength and spreading throughout Germany, Nazi organizations were also being created within the FC Danzig, adding to the persecution of the Slavic Poles. In 1933 the Nazi party won the majority of seats in the governing body of FC Danzig.

In 1934, after Hitler gained the role of Fuhrer, Germany and Poland experienced a rare thawing of relations with the signing of the German-Polish Non-Aggression Pact. This was soon following by Hitler approaching the powers that be. 'Let's do away with all this "Free City" nonsense. Danzig is a German city with a German population. Everyone will be happier if Danzig is once again in The Reich.'

Everyone but POLAND, who said no, no, no. So the status quo was to remain, and Hitler took his ball and went home. Where he fumed and plotted. And made some backdoor deals.

The entire world could feel the tension, and Europe prepared mentally for war. Poland, who was allowed the military transport site at the dock of Danzig -- but through the terms of the treaty was not allowed to improve the site -- worked secretly for three years during the 1930s to fortify the buildings in preparation for attack.

Persecution of the Poles in the FC of Danzig increased during the 1930s. The Post Office was forced to employ a two man team on each mail route -- the mail carrier, and an armed guard (a practice that was heartily ridiculed in the Danzig German press). The Postal Officers (whose job titles actually were military titles) began secretly training with weaponry.

Everyone knew something was going to happen, and it was even stated by the British First Lord of the Admiralty Alfred Duff Cooper, "It is likely that the first shots of the war will be fired here."