After Germany declared war on Russia to help Austria-Hungary (who was attacked by Russia after they attacked Serbia), France made clear their intent to stand by their ally (Russia, obviously), so Germany declared war on them, too, planning to take them out then go after Russia to prevent a two-front war. Unluckily for Germany, Russia prepared pretty quickly so Germany had to send troops to the Eastern Front as well and fight a two-front war.
England and France declared war on Germany in WWI and WWII.
Because Germany attacked France
the invasion of Poland by Germany
The invasion of Poland .
Quite the opposite, the US did not declare war on Germany, but Germany declared war on them. They did this to honor their alliance with Japan after the Pearl Harbor attacks.
Why did germany declare war on france?
It didn't. Germany started invading other countries which made France and the UK declare war on Germany.
France, Germany, and Britain vs. Russia and Serbia.
i wanty the answering
France declared war on Germany on 3 September 1939, a few hours after Britain.
Its invasion of poland in 1939.
It was when Germany invaded Poland.
Sep 3rd, 1939
Britain and France.
Britain and France
declare war on Germany
France and Britain had promised to declare war if Germany tried to obtain anymore territory. And they kept that promise when Poland was invaded.