The 1939 invasion of Poland caused Britain to declare war on Germany, which started WWII.
the invasion of Poland in Sept 1939
As dictated by a promise made, France and Britain immediately declared war on Germany after the invasion of Poland.
England did not declare war on Germany. Great Britain did. England is not an independent nation. Nonetheless the Answer is still Poland.
Britain and France declared war on Germany on September 3, 1939. The reason was because Germany had launched a military invasion of Poland two days earlier, even though Britain and France had told Germany not to do so.
The dislike of Germany from multiple countries began after their invasion of Poland. During WWII, the first two countries to declare war on Germany were Great Britain and France.
The German invasion of Poland on September 1, 1939.
When the Germans violated British neutrality to reach France, Britian declared war on Germany.
Britain and France on 3rd September 1939 and Poland 2 days before on 1st September
1939
The German invasion of Poland on 1 September 1939.
The German invasion of Poland... complements of THE DENNIS JONESGermany invading Polandthe German invasion of Poland