Who established the Open Door Policy regarding trade with China?

The Open Door Policy, which aimed to ensure equal trading rights for all nations in China and maintain China's territorial integrity, was established by John Hay, who served as Secretary of State under President William McKinley and later Theodore Roosevelt. In 1899, Hay sent a series of notes to various world powers to assert that all nations should equally respect Chinese trade and prevent any single nation from monopolizing the country’s assets. This policy reflected America’s growing interest in China as a market and its desire to prevent European powers from further dividing China into spheres of influence.

John Hay’s efforts were critical in shaping U.S. foreign policy in the early 20th century and cemented America's role in Chinese trade. His diplomatic approach to this issue laid the groundwork for subsequent U.S. relationships not only with China but also with other countries that had interests in the region.