Sahyoe Hasegawa was born in 1567 in Nagasaki. He was said to have been the son of a carpenter of the province of Hitachi. His younger sister was a favored concubine of Tokugawa Ieyasu and had received permission to engage in shuin (“vermilion-seal”) trade, foreign trade carried out in officially licensed ships.
Hasegawa entered the service of Tokugawa Ieyasu in 1602 and in 1606 succeeded his deceased elder brother Shigeyoshi as bugyd (governor) of Nagasaki. In this post he had occasion to deal with the foreign traders who came to the port and proved himself highly capable in managing the port, supervising the foreign trade carried out by the Japanese "vermilion-seal” vessels and vessels from abroad and enforcing the prohibitions against Christianity.
In 1608, a trading vessel belonging to Arima Harunobu, the lord of Hizen, put in at the port of Macao. A dispute arose between the crew and the citizens of Macao, which resulted in the death or injury of many of the Japanese. The following year, the commander of the trading fleet, Andre Pessoa, came to Nagasaki in the vessel Madre de Devs to request the shogunate to prohibit Japanese ships from calling at Macao. Hasegawa, however, acting in conjunction with Arima Harunobu, attacked the vessel. Pessoa and his crewmen, realizing that the situation was hopeless, set fire to their powder casks and blew themselves up along with their ship.
In 1614, when Tokugawa Ieyasu attacked the Toyotomi family at the Winter Siege of Osaka Castle, Hasegawa was ordered by the shogunate to request the daimyo of the Kyushu region to dispatch their forces. The following year, he was transferred to the post of magistrate of the city of Sakai. His nephew Gonroku Fujimasa succeeded him as governor of Nagasaki and proved equally diligent in enforcing the prohibitions against Christianity. Hasegawa was said to have played an important role in promoting the general use of the abacus. He is buried in the Scikyo-ji in Sakamoto in Shiga Prefecture.
