Imperialism was one of the first conflicts that lead up to World War I. Europe rushed to claim un\colonized land in China and Africa, in the 1800s. It caused tension in Europe and rivalries became stronger between countries. With rivalries between countries getting stronger, this lead to Militarism. “By the early 1900s in Europe, diplomacy had taken a backseat in militarism.” This meant that countries such as France, Germany, Austria-Hungary, Great Britain and Russia started to rapidly build up their armies. This made the possibility for war much greater. Nationalism occurred when the powerful countries in Europe acted in their own country's interest. This caused a conflict when their national interest was different from other countries.
The complicated web of alliances in Europe, were a big cause of why around 100 countries got involved with World War I. It started in the late 19th century when many of Europe’s countries were starting to form alliances for protection. Austria-Hungary and Germany became alliances and would later join with the Ottoman Empire. They were known as the Central Powers. They fought against Serbia, Russia, and