Germany and the Soviet Union jointly invaded Poland on Sept 1, 1939. Britain and France had signed a treaty with Poland, prior to this, which obligated that both countries declare war on Germany. Actually, the Soviet Union invaded the eastern region of Poland about a week or so later, as stipulated in the Germa-Russian treaty in Aug 1939.
When the Germans violated British neutrality to reach France, Britian declared war on Germany.
UK Declaring War on GermanyGreat Britain and Poland had a mutual aid treaty that required either country to come to the aid of the other in the event of war. When Germany invaded Poland, Britain (and the Commonwealth) was obligated to come to the aid of Poland by declaring war on Germany. Here is more input:Germany kept breaking the Treaty of Versailles that ended WW1. Finally when Germany invaded Poland, England had no choice but to declare war. Appeasement by Neville Chamberlain had failed and only encouraged Germany and Hitler, so England knew that Hitler was bent on domination of Europe. England could not allow this to happen.Because Germany invaded Poland. Britain had earlier guaranteed Poland's independence and as a result of German's invasion of Poland, declared war on Germany.
They did nothing until Japan bombed Pearl Harbor. Then the US Congress finally allowed FDR to send troops to the European Theater of Operations to help Britain defeat the Nazis. The US troops went to Africa to join the Brits in that effort. The rest is history.
Three things that led the Congress and President Roosevelt to declare war on Germany were:Japan attacked the United States. This was the impetus that finally allowed the president and congress to declare war on both Germany and Japan.Britain was desperate for help. Winston Churchill had sent numerous requests for the assistance of the US.Hitler's invasion and murders in other countries moved the US to stop Hitler in his tracks.
Germany
The German invasion of Poland on September 1, 1939.
When the Germans violated British neutrality to reach France, Britian declared war on Germany.
The German attack on Poland on 1 September 1939
1) The British found a letter written by Germany that tried to get Mexico to declare war on the USA, and 2) Germany said they were going to resume unrestricted submarine warfare and sink any ships (civilian or military) sailing between the USA and England. These two actions finally provoked President Wilson to ask the Congress to declare War on Germany.
Germany, Britain and France all controlled it, with it finally gaining independence from France in 1960.
France didn't do anything, rather it failed to take steps to prevent the war. Germany spent the decade of the 1930's building up its military in violation of the Versaille Treaty, announcing for all to hear that it was willing and able to use force to take whatever it wanted from its neighbors, and that it wanted everything, and finally threatening force to swallow Austria and Czechoslovakia. through all this France, and Britain, took no action whatsoever and signed whatever Hitler wanted them to to legitimise Germany's aggressions. only when Germany openly attacked Poland did France and Britain finally realize they would have to fight in order to stop Nazi aggression. The Germans caused the war by attacking their neighbors. France and Britain did nothing to anyone, but they failed to act against Germany soon enough to prevent a wider war.Michael Montagne
1825
Germany first failed to win the Battle of Britain, then Germany failed to capture Moscow, finally Germany lost the Battle of Stalingrad and Germany began the slow, but, steady retreat back to Berlin.
Japan
Around 407AD, the latest usurper, Constantine III, left Britain, taking the remaining elements of the army with him.
UK Declaring War on GermanyGreat Britain and Poland had a mutual aid treaty that required either country to come to the aid of the other in the event of war. When Germany invaded Poland, Britain (and the Commonwealth) was obligated to come to the aid of Poland by declaring war on Germany. Here is more input:Germany kept breaking the Treaty of Versailles that ended WW1. Finally when Germany invaded Poland, England had no choice but to declare war. Appeasement by Neville Chamberlain had failed and only encouraged Germany and Hitler, so England knew that Hitler was bent on domination of Europe. England could not allow this to happen.Because Germany invaded Poland. Britain had earlier guaranteed Poland's independence and as a result of German's invasion of Poland, declared war on Germany.
2 main reasons. Germany kept sinking ships with Americans on them (such as RMS Lusitania). And Germany plotted with Mexico to conquer parts of US and give land back to Mexico.