The International Opium Convention, signed at The Hague on January 23, 1912 during the First International Opium Conference, was the first international drug control treaty. The United States was unsuccessful in its attempts to have cannabis included in the 1912 Convention.[1] It was registered in League of Nations Treaty Series on January 23, 1922.[2] The United States convened a 13-nation conference of the International Opium Commission in 1909 in Shanghai, China, in response to increasing criticism of the opium trade. The treaty was signed by Germany, the United States, China, France, the United Kingdom, Italy, Japan, the Netherlands, Persia, Portugal, Russia, and Siam.