Causes of the Great War

…

…Russia. Once France tried to defend Russia, Germany declared war on them as well, and attacked through Belgium, breaching the Treaty of London, which stated, that many nations, including Britain and Germany would defend Belgium against future attacks. And finally, on August 4, 1914, Britain declared war on Germany. One nation, Austria-Hungary, trying to take over another nation, the Balkans, proved to be the start of all the countries in the alliances declaring war on each other.