The League of Nations was the first international organisation established to promote world peace and cooperation. It was founded in 1920 as a direct result of the devastation caused by World War I (1914-1918).
The creation of the League was driven by the desire to prevent a repeat of the catastrophic conflict that had killed millions across Europe and beyond. United States President Woodrow Wilson was one of its leading advocates, and the League was formally established through the Treaty of Versailles, signed in June 1919, which ended the war. The League began operations in January 1920 with its headquarters in Geneva, Switzerland.
The Cold War was a post-World War II rivalry (roughly 1947-1991) and had no connection to the League's founding. The Industrial Revolution was an economic and technological transformation that began in the late 18th century, long before the League existed. World War II (1939-1945) actually exposed the League's failure to maintain peace, leading to its replacement by the United Nations in 1945.
The correct answer is World War I, because the League of Nations was created specifically to address the failures in diplomacy and collective security that allowed that war to occur.
