After Germany declared war on Russia, France with its alliance with Russia prepared a general mobilization in expectation of war. On 3 August 1914, Germany responded to this action by declaring war on France. Germany, facing a two-front war, enacted what was known as the Schlieffen Plan, that involved German armed forces needing to move through Belgium and swing south into France and towards the French capital of Paris. This plan was hoped to quickly gain victory against the French and allow German forces to concentrate on the Eastern Front. Belgium was a neutral country and would not accept German forces crossing its territory. Germany disregarded Belgian neutrality and invaded the country to launch an offensive towards Paris. This caused Great Britain to declare war against the German Empire, as the action violated the Treaty of London that both nations signed in 1839 guaranteeing Belgian neutrality and defense of the kingdom if a nation reneged.