Several interrelated long-term and immediate factors contributed to the outbreak of World War 1. Rising nationalism across Europe upset the traditional balance of power and led countries like Germany and Serbia to seek to expand their territory. An arms race between European powers exacerbated tensions, as did tight networks of alliances that pulled more countries into local conflicts. The assassination of Archduke Franz Ferdinand provided the spark that ignited hostilities after Austria-Hungary issued demands on Serbia, leading Germany, Russia, France and eventually other allies to enter the fray.