In 1543, during the wars of the
Sengoku period, the Portuguese landed in Japan for the first time, and soon spread Christianity throughout Japan from
Kyushu. Regional
daimyō, or feudal lords, were eager to trade with the Portuguese for their European
arquebus, while the Portuguese saw the Japanese as potential converts to the Christian religion, preferring to trade with those who converted. Trade and religion thus tied, many
daimyo became Christian, such that at the eve of unification of Japan by
Tokugawa Ieyasu in 1600, as many as 14
daimyo at the time were baptised. Even when some of those Christian
daimyo supported Ieyasu at the decisive
Battle of Sekigahara, many other Christian
daimyo rallied around the heir of
Toyotomi Hideyoshi. In any case, the question remained for the unifier of Japan where the Christian lords' loyalties ultimately lay.
Arima Harunobu, the daimyo of
Hinoe Domain, became one of the most important supporters of the Church in post-Sekigahara Japan as Tokugawa Ieyasu became
shōgun and purged his enemies, like the influential Christian lord
Konishi Yukinaga. In the first decade of the
Tokugawa shogunate, Arima Harunobu was able to keep his fief and was given the right to send
red seal ships to trade overseas. In one of these voyages in 1608, the crew of a red seal ship belonging to Harunobu became involved in a deadly quarrel in
Portuguese Macau after coming back from Cambodia to fetch a cargo of
agarwood for Ieyasu, resulting in 50 Arima samurai being killed under the orders of the
Captain-major André Pessoa (
Red Seal Ship incident). The same captain-major came to Nagasaki on the
Nossa Senhora da Graça to trade in 1609, and Arima Harunobu took this opportunity to seek permission from Tokugawa Ieyasu to avenge his dead men. Ieyasu acceded - although the Portuguese controlled much of the
Nanban trade, Ieyasu sought to decouple the close relationship between that trade and Christianity. Arima Harunobu thereupon took a flotilla of 1,200 men to attack Pessoa in Nagasaki, and after a three-day engagement, the
Nossa Senhora da Graça sank in an explosion bringing Pessoa down with it on January 6, 1610. However, this victory for Harunobu soon led to his downfall. ==Intrigues==