From the mid-nineteenth century to the turn of the twentieth century, trade was conducted throughout East Asia not only with Europe and the United States but also among open ports and their hinterlands and coastal regions. Multilateral trading activity was based on commercial treaties that ushered in changes in the Chinese tributary system. 1 After its opening in the 1850s, Japan extended its economic ties throughout East Asia by vigorous participation in the long-established commercial networks of Chinese merchants and overseas Chinese. 2