1919 Treaty of Versailles

With the Treaty of Versailles, which officially ended World War I and established the League of Nations (forerunner of the United Nations) in 1919, the subsequent decade saw an increasing attempt to regulate warfare by international agreement. For the first time in the history of warfare there existed a truly international organization wherein sovereign nations could agree on rules that all states should abide by. Various armament reductions imposed on the Central powers were agreed to by all sides and German chemical capabilities were specifically targeted.