Why did Britain fight with Hitler?

Answer 1

In the summer and fall of 1940, German and British air forces clashed in the skies over the United Kingdom, locked in the largest sustained bombing campaign to that date. A significant turning point of World War II, the Battle of Britain ended when Germany's Luftwaffe failed to gain air superiority over the Royal Air Force despite months of targeting Britain's air bases, military posts and, ultimately, its civilian population. Britain's decisive victory saved the country from a ground invasion and possible occupation by German forces while proving that air power alone could be used to win a major battle.

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"Why did Britain have to fight Hitler?" - because Britain and France had a treaty with Poland, that they would come to Poland's aid should Poland ever be invaded by Another Country. Once Germany invaded Poland, Britain and France had to honour the treaty.

Answer 2

In the late 1930's, Britain and France had a defence agreement with Poland which stated that they would come to its aid if it was attacked. On 1 September 1939, German farces invaded Poland, so on 3 September 1939, Britain and France declared war on Germany.