This was called the ‘Three Emperors League’. In 1890 Wilhelm II became Kaiser of Germany. Austria and Russia were fighting over who should rule the Balkans. IN the end, Germany sided with Austria, which led to the ‘Three Emperors League’ breaking and Germany and Austria formed an alliance with Italy (‘Triple Alliance’).
Russia then formed an alliance with France, this meant that Germany had enemies on both sides, which could result ‘War on two fronts’. Since France was in the west and Russia was in the East.
Germany tried to form an alliance with Britain to scare off Russia and France. But when Britain knew that Germany was expanding their navy, they took this as threat towards them since Britain had the largest navy, even more than the world’s put together. This left Britain the only country without an alliance. Germany offered Britain an alliance with them, but they also had to stop building their navy. Britain disagreed and formed an alliance with France. Germany made up the Schlieffen Plan. Because France and Russia were allies, war with one of them means war with both.
If Germany goes into war with either one, they should move first, defeat the French by sending the army through Belgium then unleash the whole German army on Russia. In this way, Germany could avoid a “war on two fronts”. Britain signed an alliance with Russia in 1907 which created the “Triple Entente of Russia, France and Britain. This matched the “Triple Alliance ” of Germany, Austria and Italy. In 1908, a British newspaper called the Daily Telegraph interviewed the Kaiser og Germany. He wanted to present himself as “friend of England” but lost his temper when he remembered the times that Britain had refused his offer of an alliance.
... Britain and France would mean the probable defeat of Germany at war, but at the possibility that Britain and France might leave Russia to fight Germany ... more attractive than the alliance. He would therefore have time for as long as it takes Germany to deal with the ... seen as a symbol of an alliance or friendship of any sorts between Germany and Russia, the two countries stood diametrically opposed ...
He called British “Mad as March Hares ” which made Britain very mad. This destroyed any chance of an alliance forming between Germany and Britain. The Kaiser of Germany gave Austria a “Blank Cheque” in July 1914 and promised them to give them full support to whatever happens. Russia started to mobilize her army. Kaiser Wilhelm of Germany and Tsar Nicholas of Russia exchanged messages and tried to sort things out. But when Germany asked Russia to demobilize, Russia replied that only Austria was being threatened, not Germany. Germany did not want France to get involved and asked France to promise that they wouldn’t, they did not reply.
Britain did not want to get involved unless Belgium was going to be attacked. When Germany declared war on Russia, they had no choice but to declare war on France too because France and Russia were allies. They would attack Germany even if they did not declare war because they were allies and would create ‘The war on two fronts’. But when Germany barged into Belgium as part of the Schlieffen Plan, even though Britain then promised to defend Belgian neutrality, which resulted to Britain declaring war on Germany. And this is what started World War 1.