Actually Germany backed the Austria-Hungarian empire that wanted to attack Serbia because of the assassination of Arch Duke Franz Ferdinand.
Russia was allied with Serbian Nationals and mobilized their troops against A-H empire.
Germany was an ally of the A-H empire and mobilized their troops against Russia.
France and Great Britain had an defensive alliance with Russia. They would come to Russia's aid if they were attacked, so they started to mobilize their troops just in case.
Germany felt threatened by their mobilization and started to mobilize troops along the border with France.
A-H moved on Serbia and Russia attacked A-H empire.
Germany then attacked Russia.
France and Great Britain honored their treaty with Russia and declared war on the A-H empire and Germany.
Germany became the aggressor against France and Great Briton by physically attacking them first.
Actually all of this and World War II can be traced back to a Roman Legion that was wiped out in the Rhineland. You will need to do some research to figure that out but it is basically true.
Great Britain and France declared war on Germany in 1939, because germany had invaded land that Great britain had to protect for france.
Great Britain and France declared war on Germany in 1939, because germany had invaded land that Great britain had to protect for france.
Great Britain and France declared war on Germany in 1939, because germany had invaded land that Great britain had to protect for france.
Belgium .
In 1914 when Germany violated Belgian sovereignty to attack France, Britain came to Belgium's aid.
Great Britain and France have unitary governments; Germany has a federal government.
Britain and France declared war on Germany on 3 September 1939 following the German attack on Poland two days earlier.
Great Britain and France declared war on Germany on September 3, 1939, in response to Germany's invasion of Poland on September 1, 1939. This invasion violated agreements made by Germany to respect Polish sovereignty, and both Britain and France had pledged to support Poland in the event of an attack. The declaration marked the beginning of World War II in Europe.
Great Britain and the United States were allies to defeat Germany so the US would not attack Great Britain.
France and Britain declared war on Germany.
The more important reason for Britain joining World War 1 was the Schlieffen Plan, that Germany had written up. The plan involved Germany attacking on two fronts; Russia and France. Almost immediately this would of set sparks off within the Triple Entente; Great Britain, Russia and France. The biggest fault of the plan was that Germany would have to go through Belgium to attack France. In 1839, Britain signed a treaty with France stating that they would help Belgium, who were neutral, if they were ever invaded. With Germany wanting to pass through Belgium, Britain were forced to declare war on Germany, something which the Germans had not expected at all. If Britain had left it, essentially Germany would of invaded both France and Belgium, and then would of been able to invade Britain from the South. Germany could of won World War One if Great Britain didn't attack.
Great Britain, France, and Germany.