- Nationalism: Intense nationalistic sentiments and rivalries among European countries contributed to tensions and fueled the desire for expansion and dominance.
- Imperialism: The competition for colonies and the pursuit of economic and territorial expansion led to increased tensions between European powers, particularly in Africa, the Balkans, and the Middle East.
- Militarism: The buildup of military strength and the arms race among major European powers created an atmosphere of fear and suspicion, as each country sought to protect its interests and maintain a balance of power.
- The System of Alliances: A complex network of alliances and ententes developed among European countries, in which each country pledged to support its allies in case of war. This web of alliances contributed to the spread of conflict and the inability to resolve disputes peacefully.
- The Assassination of Archduke Franz Ferdinand: The heir to the Austro-Hungarian throne, Archduke Franz Ferdinand, was assassinated by a Serbian nationalist in June 1914. The incident served as the immediate trigger for the outbreak of war, leading to a chain of events that culminated in the declaration of war by Austria-Hungary against Serbia and the subsequent involvement of other European powers.
These factors, combined with the failure of diplomatic efforts and the prevailing climate of militarism and nationalism, ultimately led to the outbreak of World War I in August 1914.