Diplomatic history of World War I

World War I was a very big war that happened in the early 1900s. It involved a lot of countries all over the world and lasted four years (1914 - 1918). The diplomatic history of World War I explains how these countries interacted with each other before, during, and after the war. Before the war, countries made agreements about how they would help each other if a war happened and tried to stay friendly with each other. During the war, countries made agreements about how to try to solve the problems that caused the war and how to end it. After the war ended, countries worked together to make sure something like the war never happened again. They also made agreements to help build peace and prevent another war.