The document summarizes key events from June to August 1914 that led to the outbreak of World War 1. It describes the assassination of Archduke Franz Ferdinand which increased tensions between Austria-Hungary and Serbia. Austria-Hungary issues an ultimatum to Serbia and declares war after Serbia orders mobilization. Germany promises support for Austria-Hungary and demands an end to Russian mobilization. Germany declares war on Russia and invades neutral Belgium, bringing Britain into the war against Germany. Over the course of a few weeks in August, the major European powers declare war on each other and the first battles of WWI begin across Europe and colonies.