The Treaty of Wanghia was the first of the unequal treaties imposed by the United States on the Qing dynasty. By the terms of the diplomatic agreement, the United States received the same privileges with China that Great Britain had achieved under the Treaty of Nanking in 1842. The United States received additional privileges as well, including the right to cabotage on preferential terms and the expansion of extraterritoriality. Imperial China's Qing dynasty signed the treaty with the United States on July 3, 1844, in the Kun Iam Temple. The treaty was subsequently passed by the U.S. Congress and ratified by President John Tyler on January 17, 1845. The Treaty of Wanghia was formally in effect until the signing of the 1943 Sino-American Treaty for the Relinquishment of Extraterritorial Rights in China.

Unequal treaties refer to a series of treaties signed during the 19th and early 20th centuries, between China and various foreign powers. The agreements, often reached after a military defeat or a threat of military invasion, contained one-sided terms, requiring China to cede land, pay reparations, open treaty ports, give up tariff autonomy, legalise opium import, and grant extraterritorial privileges to foreign citizens.