|The German-Polish Crisis began in March, when the German government demanded that Danzig be turned over to Germany. In addition, the Germans demanded the right to construct an extra-territorial railroad across the corridor. The Poles refused, and the French and British pledged to aid the Poles. After the signing of the Non-Aggression Pact, all attempts at negotiations failed and the Germans and Poles mobilized for war. The British and the French did the same, reasserting that they would come to the defense of Poland.
On September 1st, the Germans attacked, and on September 3rd, Great Britain and France declared war on Germany.