Cao Rulin was Vice-Minister of Foreign Affairs of the Beiyang Government, and an important member of the pro-Japanese movement in the early 20th century. In 1915, he took Yuan Shikai's orders and signed the infamous "Twenty-One Demands" treaty with Japan. Cao Rulin was part of the Chinese envoy attending the Paris Peace Conference. At the conference many concessions were made to Japan that were unfavorable to China. Wikipedia
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