Answer: The League of Nations
Explanation: Image result for What was the first international league called? Who were the countries in the league?
The League began organizational work in the fall of 1919, spending its first 10 months with a headquarters in London before moving to Geneva. The Covenant of the League of Nations went into effect on January 10, 1920, formally instituting the League of Nations. By 1920, 48 countries had joined.
