The First World War, often referred to as the Great War, was a worldwide conflict that spanned from 1914 to 1918. It involved numerous major powers and resulted in extensive loss of life and widespread destruction. A significant factor contributing to the war’s outbreak was the ambition to preserve the balance of power in Europe.

Preservation of balance of power as the reason for first world war

1. Formation of Alliances such as the Triple Alliance (Germany, Austria-Hungary, and Italy) and the Triple Entente (Britain, France, and Russia), was a strategic move to balance military strength in Europe. 
2. Germany’s rapid economic and military growth was perceived as a threat by other European powers, particularly Britain. The naval arms race between Britain and Germany exemplified this power struggle, escalating tensions that contributed to the outbreak of war.
3. Colonial Rivalries: Competition for colonies and global influence intensified rivalries among European nations. Incidents such as the Moroccan Crises (1905 and 1911) highlighted these tensions, as conflicts over African territories further strained relationships between France and Germany.
4. Austro-Hungarian and Russian Rivalry in the Balkans: The Bosnian Crisis of 1908, when Austria-Hungary annexed Bosnia, angered Russia and Serbia, exacerbating existing tensions in the Balkans. This rivalry played a crucial role in destabilizing the region and contributing to the war’s outbreak.
5. France’s Desire for Revenge: After losing Alsace-Lorraine to Germany in the Franco-Prussian War, France sought alliances with Russia and Britain to contain Germany’s growing power. This desire for revenge fueled France’s involvement in the conflict.
6. Preservation of Empires: The fear of losing imperial influence motivated British involvement, highlighting how imperial ambitions were intertwined with the balance of power considerations.

Other Reasons of First World War

1. Nationalism and ethnic tensions: rising nationalism in the Balkans and killing of Franz Ferdinand was rooted in serbian nationalism, which had less to do with European balance of power struggle. 
2. Economic rivalry,desire for market dominance and resource control particularly between Britain and Germany especially in Africa and Asia was also a key reason for world war.
3. Imperialism: war was essentially fought over retention and expansion of colonies. Scramble for Africa and control over Asian colonies led to long standing tensions between these imperial powers.
4. Militarism in pre pre-war environments like Germany’s Schlieffen Plan, which aimed for a rapid attack on France from Belgium. Arm race among European powers fostered an environment of distrust and war.
5. Diplomatic failures as initial alliances like the Franco-Russian alliance of 1894 created an environment of mistrust and escalated confrontations against germany.

While the First World War was primarily fought to preserve the balance of power, it was not the sole cause. Nationalism, imperialism, economic rivalry, and domestic pressures also played significant roles, making the balance of power a central but not exclusive factor in the conflict.