Pho Hien (today called Hung Yen) was a major port in northern Vietnam (Tonkin) in the 16th to 17th centuries. The town is located roughly 50 km southeast of Hanoi (Thang Long), and sits on the east bank of the Red River.
Eleven red seal ships licenses were issued between 1606 and 1614 by the Tokugawa shogunate for Japanese, Chinese, and European merchants based in Japan to trade with northern Vietnam, then under the control of the lords of the Trinh family. By 1634, this number had risen to a total of 35 licenses. Like Hoi An in central Vietnam, and other ports in the region, the main export was silk, and the main import silver.
War broke out between the Trinh and the Nguyen lords of central Vietnam in 1627, and the Nguyen successfully petitioned the Tokugawa to sever formal ties with the Trinh, and to restrict trade with northern Vietnam. As a result, Japanese trade activity in northern Vietnam declined considerably, though by the late 1630s, only a decade later, the shogunate's policy of maritime restrictions would cause Japanese trade in Southeast Asia to decline almost entirely.
The Trinh invited the Dutch East India Company to establish a factory at Pho Hien in 1637. The Dutchmen were guided through the necessary court rituals by a Japanese woman called Ura-san, who also served as their interpreter. Having established relations, however, the Dutch were still obliged to go through Japanese intermediaries both for their interactions with the Trinh authorities, and with Vietnamese silk producers; the Trinh reserved the privilege of direct contact with silk producers for the Japanese.
- Geoffrey Gunn, History Without Borders: The Making of an Asian World Region, 1000-1800, Hong Kong University Press (2011), 229-230.