as soon as japan agreed to open up to foreign influence, the tokugawa "shōgun" government initiated an active policy of assimilation of western naval technologies. in 1855, with dutch assistance, the shogunate acquired its first steam warship, the "kankō maru", which was used for training, and established the nagasaki naval training center. in 1857, it acquired its first screw-driven steam warship, the "kanrin maru".