The Edo Shogunate was forced to conclude unequal treaties, namely, the Treaty of Peace and Amity between the United States and Japan and the Treaty of Amity and Commerce between the United States and Japan, which prescribed the opening of ports including Nagasaki, Shimoda, Hakodate and Yokohama, and approval of extraterritoriality of foreign residents, and therefore the revisions of the treaties were a diplomatic issue in the early Meiji period.
江戸幕府が日米和親条約や日米修好通商条約で長崎、下田、箱館、横浜などの開港や在留外国人の治外法権を認めるなどの不平等条約を結ばされ、明治初期には条約改正が外交課題となっていた。